U.S. patent application number 12/778585 was filed with the patent office on 2010-11-18 for device for compressing a stent and a system as well as a method for loading a stent into a medical delivery system.
Invention is credited to Johannes Jung, Arnulf Mayer, Helmut Straubinger.
Application Number | 20100292779 12/778585 |
Document ID | / |
Family ID | 43069152 |
Filed Date | 2010-11-18 |
United States Patent
Application |
20100292779 |
Kind Code |
A1 |
Straubinger; Helmut ; et
al. |
November 18, 2010 |
DEVICE FOR COMPRESSING A STENT AND A SYSTEM AS WELL AS A METHOD FOR
LOADING A STENT INTO A MEDICAL DELIVERY SYSTEM
Abstract
The invention relates to a device (1) for compressing a stent
(100) with a prosthetic heart valve affixed as needed thereto. In
order to achieve a compressing of the stent (100) with a prosthetic
heart valve affixed as needed thereto to a diameter enabling it to
be received in a catheter tip of a medical delivery system without
running the risk of damaging the stent (100) or the prosthetic
heart valve affixed as needed thereto during the compressing of the
stent (100), the device (1) comprises a compressing mechanism (10)
within which a stent (100) to be compressed can be at least partly
accommodated, wherein the compressing mechanism (10) is designed so
as to exert a defined compressive force in radial direction on at
least parts of a stent (100) at least partly accommodated in the
compressing mechanism (10) such that the cross-section of the stent
(100) is reduced to a predefinable value at least at certain
areas.
Inventors: |
Straubinger; Helmut;
(Aschheim, DE) ; Jung; Johannes;
(Pforzheim-Huchenfeld, DE) ; Mayer; Arnulf; (Markt
Schwaben, DE) |
Correspondence
Address: |
FINNEGAN, HENDERSON, FARABOW, GARRETT & DUNNER;LLP
901 NEW YORK AVENUE, NW
WASHINGTON
DC
20001-4413
US
|
Family ID: |
43069152 |
Appl. No.: |
12/778585 |
Filed: |
May 12, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61178701 |
May 15, 2009 |
|
|
|
Current U.S.
Class: |
623/1.23 |
Current CPC
Class: |
A61F 2/2427 20130101;
Y10T 29/5367 20150115; Y10T 29/53878 20150115; A61F 2/95 20130101;
A61F 2/9522 20200501; Y10T 29/53952 20150115; A61F 2/2412
20130101 |
Class at
Publication: |
623/1.23 |
International
Class: |
A61F 2/84 20060101
A61F002/84 |
Claims
1. A device for compressing a stent, comprising: a first component
including a first hollow portion; a second component including at
least one elongate finger that is at least partially disposed
within and configured to be selectively translatable with respect
to the first hollow portion; and a third component including a
second hollow portion at least partially surrounding and configured
to be selectively translatable with respect to the first hollow
portion; wherein an inner diameter of at least a portion of the
third component is configured to be selectively reduced to
selectively compress at least a portion of the stent.
2. The device of claim 1, wherein: the third component includes an
inner component and an outer component; the inner component
includes an inner surface configured to selectively engage the
stent; and the outer component at least partially surrounds a
portion of the inner component.
3. The device of claim 2, wherein the outer component is configured
to be rotatable with respect to the inner component such that
rotation in a first direction is configured to selectively reduce
an inner diameter of the inner component and selectively compress
at least a portion of the stent.
4. The device of claim 2, wherein: the inner component includes a
first end and a second end; the first end is the portion of the
inner component that is at least partially surrounded by the outer
component; and the second end includes a conical shape.
5. The device of claim 2, wherein the outer component includes an
inner surface having a saw-tooth shape about a circumference
thereof.
6. The device of claim 5, wherein the saw-tooth shape includes a
plurality of step portions and a plurality of arcuate incline
portions.
7. The device of claim 5, wherein the inner component further
includes an outer surface and a plurality of lugs extending
radially outward therefrom and configured to engage the inner
surface of the outer component.
8. The device of claim 1, wherein the at least one elongate finger
includes a plurality of elongate fingers.
9. The device of claim 8, wherein the plurality of elongate fingers
consists essentially of three elongate fingers.
10. The device of claim 1, wherein the at least one elongate finger
is selectively translatable between a retracted position and an
extended position, with respect to the first hollow portion.
11. The device of claim 10, wherein the at least one elongate
finger is configured to expand radially outward with respect to the
first hollow portion when the at least one elongate finger is
selectively translated from the retracted position to the extended
position.
12. The device of claim 10, wherein the at least one elongate
finger is configured to compress radially inward with respect to
the first hollow portion when the at least one elongate finger is
selectively translated from the extended position to the retracted
position.
13. The device of claim 10, wherein the second component further
includes a push-button biased with respect to the first component
such that the at least one elongate finger is biased into the
retracted position.
14. The device of claim 1, wherein the at least one elongate finger
includes an eyelet configured to be complimentary to a portion of
the stent.
15. The device of claim 1, wherein the at least one elongate finger
includes a tab extending therefrom and configured to be
complimentary to a portion of the stent.
16. A method of compressing a stent with a compressing device
having first, second, and third components, the method comprising:
longitudinally translating the second component relative to the
first component in a first direction such that a first elongate
finger translates from a retracted, compressed position to an
extended, expanded position; releasably connecting the first
elongate finger to the stent; longitudinally translating the second
component relative to the first component in a second direction
such that the first elongate finger translates from the extended,
expanded position to the retracted, compressed position to compress
at least a first end of the stent; and longitudinally translating
the third component relative to the first component such that the
third component translates from a first position longitudinally
offset from the stent to a second position at least partially
surrounding the stent.
17. The method of claim 16, wherein the second component includes a
push-button biased with respect to the first component, the method
further including actuating the push-button to affect translation
of the second component relative to the first component.
18. The method of claim 16, further including disconnecting the
first and second components from the stent after the third
component is translated to the second position by: longitudinally
translating the second component relative to the first component in
the first direction such that the first elongate finger translates
from the retracted, compressed position to the extended, expanded
position; disconnecting the first elongate finger from the stent;
and longitudinally translating the second component relative to the
first component in the second direction such that the first
elongate finger translates from the extended, expanded position to
the retracted, compressed position.
19. The method of claim 18, wherein the third component includes a
first hollow element engaging the stent and a second hollow element
at least partially surrounding the first hollow element, the method
further comprising rotating the second hollow element relative to
the first hollow element such that an inner diameter of the first
hollow element is selectively reduced to compress the stent.
20. The method of claim 18, wherein the second hollow element
includes an inner surface having a plurality of step portions and a
plurality of arcuate incline portions and the first hollow element
includes an outer surface having a plurality of lugs extending
radially outward therefrom, the method further including rotating
the second hollow element relative to the first hollow element to
radially displace the plurality of lugs as a function of the
rotational position of the plurality of arcuate incline
portions.
21. The method of claim 18, further including placing the third
component and the stent on a catheter having a tip after the third
component is translated to the second position and after
disconnecting the first and second components, wherein: a first end
of the third component extends toward the tip of the catheter; the
stent at least partially surrounds the catheter; and the third
component at least partially surrounds the stent.
22. The method of claim 20, wherein the third component includes a
first hollow element engaging the stent and a second hollow element
at least partially surrounding the first hollow element, the method
further comprising rotating the second hollow element relative to
the first hollow element such that an inner diameter of the first
hollow element is selectively reduced to compress the stent.
23. The method of claim 22, further including connecting the first
end of the stent to the catheter.
24. The method of claim 23, further including: actuating a portion
of the catheter to at least partially surround the first end of the
stent; rotating the second hollow element relative to the first
hollow element such that the inner diameter of the first hollow
element is selectively increased; and maintaining the first end of
the stent in a compressed state with the catheter.
25. The method of claim 24, further including: removing the third
component from the catheter; and replacing the third component on
the catheter such that the first end of the third component extends
away from the tip of the catheter; wherein the third component at
least partially surrounds the stent.
26. The method of claim 25, further including rotating the second
hollow element relative to the first hollow element such that the
inner diameter of the first hollow element is selectively reduced
to compress a second end of the stent.
27. The method of claim 26, further including: actuating a portion
of the catheter to at least partially surround the second end of
the stent; rotating the second hollow element relative to the first
hollow element such that the inner diameter of the first hollow
element is selectively increased; and maintaining the second end of
the stent in a compressed state with the catheter.
28. The method of claim 24, further including removing the third
component from the catheter and placing a fourth component on the
catheter, wherein the fourth component includes a third hollow
element configured to engage the stent and a fourth hollow element
at least partially surrounding the third hollow element and the
fourth component at least partially surrounds the stent.
29. The method of claim 28, further including rotating the fourth
hollow element relative to the third hollow element such that the
inner diameter of the third hollow element is selectively reduced
to compress a second end of the stent.
30. The method of claim 29, further including: actuating a portion
of the catheter to at least partially surround the second end of
the stent; rotating the fourth hollow element relative to the third
hollow element such that the inner diameter of the third hollow
element is selectively increased; and maintaining the second end of
the stent in a compressed state with the catheter.
31. The method of claim 16, wherein the first component includes a
first hollow portion, the method further including radially
expanding the at least one elongate finger outward with respect to
the first hollow portion when the at least one elongate finger
translates from the retracted, compressed position to the extended,
expanded position.
32. The method of claim 16, wherein the first component includes a
first hollow portion, the method further including radially
compressing the at least one elongate finger inward with respect to
the first hollow portion when the at least one elongate finger is
translates from the extended, expanded position to the retracted,
compressed position.
Description
[0001] This application claims priority to U.S. Provisional Patent
Application No. 61/178,701, filed May 15, 2009, the entire contents
of which are hereby incorporated herein by reference.
[0002] The present disclosure relates to a device for compressing a
stent, as needed with a prosthetic heart valve affixed thereto, as
well as a system for loading a stent, as needed with a prosthetic
heart valve affixed thereto, into a medical delivery system, in
particular the tip of a catheter of a medical delivery system. The
disclosure further relates to a method for loading a stent, as
needed with a prosthetic heart valve affixed thereto, into a
medical delivery system, in particular the tip of a catheter of a
medical delivery system.
[0003] Medical technology has long since endeavored to occlude
valvular defects such as, for example, aortic valve insufficiencies
or aortic valve stenosis, by means of non-surgical, transarterial
access; i.e. without requiring open heart surgery, with
implantation by way of catheter. In the process, various different
stent systems with various different advantages and disadvantages
have been proposed, some which can also be inserted transarterially
into the body of a patient via a catheter delivery system.
[0004] The terms "aortic valve stenosis and/or aortic valve
insufficiency" as used herein generally refer to a congenital or
acquired dysfunction of one or more cardiac valves. Such valvular
disorders can affect any of the four cardiac valves, whereby the
valves in the left ventricle or left chamber (aortic and mitral
valve) are typically more affected than those on the right side of
the heart (pulmonary and tricuspid valve). The dysfunction can be a
constriction (stenosis), an incompetence (insufficiency) or a
combination of the two (combined vitium).
[0005] Minimally-invasive forms of treatment have recently been
developed which are in particular characterized by allowing the
procedure to be performed under local anesthesia. One approach
provides for using a catheter system to implant an expandable
stent, to which a collapsible prosthetic heart valve has been
affixed, into a human body. Such an expandable prosthetic heart
valve can be guided via a delivery or catheter system to the
implantation site within the heart through an inguinal artery or
vein. After reaching the implantation site, the stent can then be
unfolded. After unfolding, the prosthetic heart valve can be
anchored in the respective blood vessel at least in an area close
to the heart, for example with the aid of anchoring hooks. The
actual prosthetic heart valve is usually positioned in the proximal
area of the stent.
[0006] For example, the WO 2004/019825 A1 printed publication
describes a heart valve stent for a heart valve prosthesis. This
stent can be introduced into the site of implantation in the
patient's heart via a medical delivery system to treat an aortic
valve stenosis and/or aortic valve insufficiency in a
minimally-invasive manner.
[0007] Known conventional systems for implanting a prosthetic heart
valve introduce an expandable stent system
transarterially/transfemorally or transapically into the body of
the patient using a medical delivery system. This type of stent
system consists for example of an expandable anchoring support
(hereinafter also referred to as "cardiac valve stent" or simply
"stent"), to which the actual prosthetic heart valve is affixed or
can be affixed, preferably at the end region nearest the heart
(proximal end).
[0008] The explanations disclosed herein with respect to a "stent
system" are also applicable to a "stent".
[0009] The term "medical delivery system" as used herein generally
refers to a medical system with which a stent system can be
advanced in minimally-invasive fashion to the site of implantation
in the patient's heart, for example to treat an aortic valve
stenosis and/or aortic valve insufficiency. In the present context,
"minimally-invasive" means a heart-lung machine is not needed when
performing the procedure on the anaesthetized patient such that not
only can the medical procedure be performed at reasonable cost, but
there is also less physical and psychological strain on the
patient.
[0010] A medical delivery system usually comprises a catheter
system by means of which a stent, as needed with a prosthetic heart
valve affixed thereto in folded state, can be introduced into the
patient's body in its folded state. For example, the medical
delivery system can exhibit a catheter tip having at least one
manipulatable receiving area at a proximal end section of the
catheter system; i.e. closest to the heart. It is moreover
conceivable for the medical delivery system to exhibit a handle at
the distal end section of the catheter system; i.e. at the end
section of the catheter system farthest from the heart and the
catheter tip, with which the at least one receiving area of the
caterer tip can be appropriately manipulated such that the
expandable stent accommodated in the catheter tip, as needed with a
prosthetic heart valve affixed thereto, can be incrementally
released from the catheter tip according to a predefined or
predefinable sequence of events.
[0011] In this disclosure, the expression "catheter system" means a
system that can be inserted into a body cavity, duct or vessel. A
catheter system thereby allows access by surgical instruments. The
process of inserting a catheter system is catheterisation. In most
uses a catheter system is a thin, flexible tube: a "soft" catheter
system; in some uses, it is a larger, solid tube: a "hard" catheter
system.
[0012] To introduce the stent system, the stent together with the
prosthetic heart valve affixed as needed thereto, is loaded into
the tip of the medical delivery system's catheter. In order to do
so, the stent, as needed with the prosthetic heart valve affixed
thereto, needs to exhibit a first predefinable shape in which the
stent or the stent and the prosthetic heart valve affixed thereto
is/are in a compressed or folded state. In its first predefined
state, the stent, as needed with the prosthetic heart valve affixed
thereto, exhibits a diameter which is essentially determined by the
diameter of the catheter tip of the medical delivery system.
[0013] For the majority of patients undergoing treatment, it is
preferable for the stent, as needed with the prosthetic heart valve
affixed thereto, to have an outer diameter of approxi-mately 7.0 mm
to approximately 5.0 mm in its first shape so that the stent system
can be introduced with a 21F delivery system (given an external
diameter of 7.0 mm) or with a 15F delivery system (given an
external diameter of 5.0 mm).
[0014] After the stent system has been released from the catheter
tip, in the implanted state respectively, the stent system exhibits
a second predefined shape in which the stent or the stent and the
prosthetic heart valve affixed thereto is/are in an expanded state.
Depending on the patient being treated, it is preferable for the
stent to exhibit a diameter of between 19.0 mm and 27.0 mm in its
second shape and implanted state.
[0015] Thus, the first shape transitions to the second shape by a
cross-sectional widening, wherein the stent stretches radially and
presses against the vascular wall of a blood vessel near the heart
and thus fixes a prosthetic heart valve affixed as needed to the
stent at the site of implantation. The cross-sectional widening can
be effected by a balloon system when the stent is implanted with
the help of a so-called balloon catheter system.
[0016] On the other hand, it is also known from medical technology
to construct the stent from a superelastic shape memory material
which is designed such that the stent can transform from a
temporary shape into a permanent shape under the influence of an
external stimulus. The temporary shape thereby corresponds to the
stent's first shape when the stent, as needed with the prosthetic
heart valve affixed thereto, is in its folded state. The permanent
shape corresponds to the stent's second shape when in its expanded
state. An example of a suitable shape memory material would be
nitinol, e.g., an equiatomic alloy of nickel and titanium.
[0017] Turning out to be disadvantageous with conventional systems
for implanting a prosthetic heart valve as known to date, however,
has been that not only the actual implantation of the stent, as
needed with the prosthetic heart valve affixed thereto, but also
the preparation needed for the implant procedure is relatively
complicated, difficult and laborious. Apart from the complicated
implanting of the stent, as needed with a prosthetic heart valve
affixed thereto, to replace an insufficient native heart valve, for
example, there is also the fundamental problem of the stent and/or
the stent and a prosthetic heart valve affixed thereto being
damaged when the stent, as needed with a prosthetic heart valve
affixed thereto, is loaded into the tip of the catheter of the
medical delivery system in preparation for the surgery. In
particular with self-expanding stent systems, the stent, as needed
with a prosthetic heart valve affixed thereto, has to be compressed
so that it will then be in its first shape and be able to be
introduced into the tip of the catheter of a medical delivery
system. This subjects the stent to considerable compressive forces
in order to overcome the self-expanding stent structure's expansion
forces and achieve the desired reduction in cross-section.
[0018] Similar circumstances however also apply to stent systems
which are implanted using balloon catheter systems.
[0019] In conjunction hereto, often likewise regarded as
problematic is that when preparing for the implant procedure, the
stent, as needed with a prosthetic heart valve affixed thereto, can
often only be loaded into the tip of the catheter of a medical
delivery system by an experienced perfusionist or by product
specialists so as to avoid damaging the stent system and so that
the stent system can be properly transformed into its defined first
shape.
[0020] Without special compressing mechanisms or loading systems,
the known systems are thus coupled with the fundamental risk of
damage to the stent system or it not properly being transformed
into its defined first shape, for example due to an oversight on
the part of the perfusionist or product specialist or some other
incident occurring during the compressing of the stent system.
Damage which occurs when compressing the stent system or when
loading the compressed stent system into the catheter tip of the
medical delivery system are often not noted until the actual
implant procedure is underway, for example when the positioning
and/or fixing of the prosthetic heart valve at the site of
implantation at the heart by means of the stent is imprecise, when
the stent will not properly expand at the implantation site in the
heart, or when it is for example deter-mined that the implanted
prosthetic heart valve cannot or not adequately enough assume the
function of the native heart valve to be replaced.
[0021] On the basis of the problems outlined above, the present
disclosure relates to a device as well as a system for compressing
a stent with which the stent, as needed with a prosthetic heart
valve affixed thereto, can be readily compressed to a desired
diameter, in particular without the risk of the stent and/or the
stent and a prosthetic heart valve affixed thereto being damaged
when compressed.
[0022] An embodiment of the present disclosure may provide a
simplified method for loading a stent, as needed with a prosthetic
heart valve affixed thereto, into the catheter tip of a medical
delivery system, in particular wherein the proper loading of the
stent into the tip of the catheter no longer depends to a
significant extent on the finesse and experience of the given
perfusionist or product specialist.
[0023] An embodiment of the present disclosure may include a device
for compressing a stent, as needed with a prosthetic heart valve
affixed thereto, whereby the device comprises a compressing
mechanism and a gripping mechanism. The device according to the
present invention allows for compressing a stent, as needed with a
prosthetic heart valve affixed thereto, to a desired diameter. The
term "desired diameter" means a diameter of the stent which allows
a proper loading of the stent into the tip of a catheter.
[0024] The compressing mechanism of the inventive device is on the
one hand configured such that the stent to be compressed can be at
least partly accommodated inside the compressing mechanism. On the
other hand, the compressing mechanism of the inventive device is
designed to exert a compressive force radial to the stent at least
on certain areas of the outer surface of the stent such that the
stent's cross-section is reduced to a predefinable value at least
at certain areas.
[0025] The device for compressing a stent, as needed with a
prosthetic heart valve affixed thereto, comprises a gripping
mechanism for forming a releasable connection with the stent to be
compressed, and in particular with an end section of said stent.
The gripping mechanism is thereby realized separately from the
compressing mechanism and is axial displaceable to be at least
partly accommodated within the compressing mechanism. The gripping
mechanism comprises an actuating element attached to a claw for
grasping the stent.
[0026] At least one, in particular externally actuatable clamping
jaw is then provided in the interior of the compressing mechanism
which is movable in the radial direction to set the internal
cross-section diameter of at least one area of the compressing
mechanism.
[0027] With respect to the specified disclosure, a system is
further disclosed with which a stent, as needed with a prosthetic
heart valve affixed thereto, can be loaded into a medical delivery
system, in particular into the tip of a catheter of a medical
delivery system. The system comprises a device for compressing the
stent and a supplementary compressing mechanism for compressing the
proximal end section of the stent. The supplementary compressing
mechanism is configured analogously to the device's compressing
mechanism.
[0028] To solve the cited second task, a method is disclosed to
load a stent, as needed with a prosthetic heart valve affixed
thereto, into a medical delivery system, in particular into the tip
of a catheter of a medical delivery system, whereby the method
comprises the method steps as specified in claim 35.
[0029] The explanations disclosed herein with respect to a stent
are also applicable to a stent with a prosthetic heart valve
affixed thereto.
[0030] Providing a gripping mechanism which is designed to create a
releasable connection to the stent to be compressed, and in
particular to an end section of the stent, may eliminate directly
touching the stent by hand when compressing the stent or loading it
into the tip of the catheter of the medical delivery system. In
this respect, the risk of a contamination and damaging of the stent
and/or the stent with the prosthetic heart valve affixed thereto
can be avoided or reduced. Instead, to grasp the stent to be
compressed, the claw of the gripping mechanism only comes into
contact with those areas of the stent to be compressed provided for
the purpose such that the risk of damaging the stent during
grasping may be significantly reduced or eliminated.
[0031] Specifically, the gripping mechanism comprises a claw, or
gripping forceps respectively, with which the stent to be
compressed can be grasped, preferably at the end section of said
stent. It is thereby preferable for the releasable connection
between the claw and the stent to occur preferably at an end
section of the stent at which the prosthetic heart valve is not
sewn or to be sewn and which serves to connect to a fastening
section in the catheter tip of the medical delivery system. This
end section of the stent is usually the distal end section of said
stent.
[0032] The terms "distal" and "proximal" as used herein are
positional or directional identifiers for the stent, each referring
to the stent in the implanted state. With a heart valve stent used
for example to treat aortic or pulmonary valve insufficiency, the
proximal end section of the stent thus faces the left or right
chamber when the stent is in its implanted state.
[0033] The gripping mechanism further comprises an actuating
element by means of which the claw can be manipulated accordingly
so as to grasp the stent to be compressed. The gripping mechanism
is thus suited to form a releasable connection with the stent to be
compressed without the stent thereby needing to be touched by
hand.
[0034] Since the gripping mechanism is axially displaceable when
being received in the compressing mechanism, this ensures that the
stent grasped with the claw of the gripping mechanism can be loaded
into the compressing mechanism. Specifically, the compressing
mechanism is designed such that the stent grasped by the gripping
mechanism can be received within the compressing mechanism and can
be displaced longitudinally relative the compressing mechanism. It
is in this way possible to load a stent releasably connected to the
claw of the gripping mechanism into the compressing mechanism such
that the stent to be compressed is at least partly accommodated
within said compressing mechanism.
[0035] The device thus allows the stent to be compressed to be
loaded into the compressing mechanism, whereby the gripping
mechanism only comes into contact with the areas of the stent so
intended for the purpose.
[0036] The compressing mechanism is designed so as to exert a
defined and radially-acting compressive force on at least one area
of the stent accommodated in the compressing mechanism so that the
cross-section of the stent to be compressed can in this way be
reduced to a predefinable value at least at certain areas. To this
end, at least one clamping jaw is provided in the interior of the
compressing mechanism which is movable in the radial direction by
appropriately manipulating the compressing mechanism in order to in
this way adjust the internal cross-sectional diameter of the
compressing mechanism to a predefinable value at least at one area
of the compressing mechanism.
[0037] By having at least certain areas of the internal
cross-sectional diameter of the compressing mechanism being able to
be changed by the at least one actuatable clamping jaw, it is
possible to have a defined compressive force act on the outer
surface of the stent at least partly accommodated in the
compressing mechanism. This compressive force counters the stent's
tensioning force acting in the radial direction so as to overcome
it and reduce the cross-section of the stent accommodated in the
compressing mechanism to the value provided for the catheter tip of
the medical delivery system according to a predefinable sequence of
events.
[0038] Preferred embodiments of the disclosed solution are
indicated in the dependent claims.
[0039] One preferred realization of the disclosed device provides
for the gripping mechanism to comprise a guide sleeve in which the
claw can be at least partly accommodated. In so doing, the claw
should be movable relative the guide sleeve upon actuation of the
actuating element. This provides an effective solution for
realizing interaction of the gripping mechanism's actuating element
with the claw in order to create a releasable connection between
the gripping mechanism and the stent to be compressed in the
compressing mechanism. Other embodiments of the gripping mechanism
are also conceivable.
[0040] In order to have the gripping mechanism be accommodated at
least partly within the compressing mechanism in defined manner, it
is preferable for the guide sleeve to comprise at least one guiding
element configured complementary to at least one of the guiding
elements allocated to the compressing mechanism. For example, it is
conceivable for at least one guiding element designated for the
guide sleeve to be configured as a guide rail extending
longitudinally to the guide sleeve.
[0041] It is hereby preferred when the at least one guiding element
allocated to the compressing mechanism is configured as a guiding
groove designed correspondingly complementary to the guide rail.
The gripping mechanism accommodated in the compressing mechanism
can thus be aligned relative to the compressing mechanism by the
guiding element allocated to the guide sleeve on the one hand and
the compressing mechanism on the other. The guiding elements extend
preferably in the longitudinal direction to the guide sleeve, the
compressing mechanism respectively, so that same allow a
longitudinal movement of the gripping mechanism relative the
compressing mechanism and thereby guide the gripping mechanism.
[0042] It is also conceivable for at least one guiding element
allocated to the guide sleeve to be configured as a guiding groove
and at least one guiding element allocated to the com-pressing
mechanism to be configured as a guide rail. Other embodiments of
the guiding elements designated for the guide sleeve, the
compressing mechanism respectively, are likewise conceivable and
covered by the present disclosure.
[0043] One preferred realization of the gripping mechanism provides
for the gripping mechanism to comprise a retaining section arranged
coaxially to the guide sleeve and connected to said guide sleeve.
The retaining section preferably serves to receive the actuating
element with which the claw of the gripping mechanism can be
correspondingly manipulated. It is for example conceivable for the
actuating element to comprise a preferably manually-actuatable
pushbutton held in the retaining section and movable in the
longitudinal direction of the gripping mechanism relative the
retaining section and relative the guide sleeve.
[0044] The pushbutton can for example be connected to the claw of
the gripping mechanism so that upon actuation of said pushbutton,
the claw of the gripping mechanism moves in the longitudinal
direction of the gripping mechanism relative the guide sleeve.
[0045] The present disclosure is however not limited to the
specific embodiments in which the actuating element comprises a
preferably manually-actuatable pushbutton. Rather, this would only
be one possible realization of the actuating element for
appropriately manipulating the claw of the gripping mechanism as
needed.
[0046] In one preferred realization of the device, the claw for
grasping the stent to be compressed comprises at least one and
preferably three gripper arms, whereby fastening means are provided
preferably on the first end section of the at least one gripper arm
which are designed to create a releasable connection with the stent
to be compressed. The number of gripper arms which the claw is to
comprise should conform to the number of fastening means provided
on the stent to be compressed and thereby serve to connect the
stent to the catheter tip of a medical delivery system.
[0047] Usually the fastening means of the stent to be compressed
are provided on the distal end section of the stent. Accordingly,
the fastening means provided at the first end section of the at
least one gripper arm are preferably designed to create a
releasable connection with the distal end section of a stent to be
compressed.
[0048] The fastening means provided on the at least one gripper arm
should be designed complementary to a retaining section, the
corresponding fastening means respectively, of the stent to be
compressed. In particular, the fastening means provided on the at
least one gripper arm are designed to form a releasable engagement
with the retaining section, the corresponding fastening means
respectively, of the stent to be compressed. For example, it is
conceivable for the fastening means provided on the at least one
gripper arm to comprise at least one projecting element, for
example at least one hook-shaped element, which can be brought into
releasable engagement with a retaining grommet of a stent to be
compressed designed correspondingly complementary thereto.
[0049] Alternatively or additionally hereto, it is likewise
conceivable for the fastening means provided on the at least one
gripper arm to comprise at least one recess formed in the first end
section of the gripper arm which can for example be configured in
the shape of a preferably oblong grommet. This recess formed in the
first end section of the gripper arm should thereby be able to be
brought into releasable engagement with a projecting retaining
element of a stent to be compressed designed correspondingly
complementary thereto. Other embodiments are also conceivable for
the fastening means provided at the first end section of the at
least one gripper arm.
[0050] In order to achieve the corresponding manipulating of the
claw upon actuation of the actuating element of the gripper means
so as to enable a grasping of the stent to be compressed, a
preferred realization of the device provides for the at least one
gripper arm to comprise the above-mentioned fastening means at its
first end section, whereby the at least one gripper arm is
connected to the actuating element of the gripping mechanism by its
second end section opposite its first end section. It is hereby in
principle possible for the at least one gripper arm to be directly
connected to the actuating element of the gripping mechanism by its
second end section.
[0051] One preferred realization of the device however provides for
the claw of the gripping mechanism to comprise a guide shaft,
whereby the first end of the guide shaft is connected to the second
end section of the at least one gripper arm, and whereby the second
end of the guide shaft is connected to the actuating element of the
gripping mechanism. The guide shaft can for example be configured
as a cylindrical body.
[0052] The providing of a guide shaft connecting the at least one
gripper arm to the actuating element of the gripper mechanism
allows for a particularly secure manipulating of the gripper arms
of the claw for grasping the stent to be compressed upon the
actuating of the actuating element. Yet other solutions for
connecting the at least one gripper arm to the actuating element of
the gripping mechanism are also conceivable.
[0053] Preferred with the latter embodiment, in which the claw
comprises a guide shaft in order to connect the at least one
gripper arm to the actuating element of the gripper mechanism, is
for the guide shaft to be accommodated within a guide sleeve
provided for the gripping mechanism. Specifically, the guide shaft
is to be accommodated within the guide sleeve such that the guide
shaft together with the at least one gripper arm connected thereto
is displaceable relative the guide sleeve. It is thereby further
preferred for guide means to be provided to guide the guide shaft
within the guide sleeve upon the displacing of the guide shaft
relative the guide sleeve. Such guide means can for example be
designed in the form of guiding surfaces.
[0054] A preferred embodiment of the device provides for the at
least one gripper arm of the claw to be connected via its second
end section to the guide shaft such that the at least one gripper
arm protrudes from the guide shaft at an angle relative to the
longitudinal direction of the guide shaft. In so doing, the at
least one gripper arm and/or a connecting area between the second
end section of the at least one gripper arm and the guide shaft are
configured so as to be elastically deformable such that upon a
displacement of the guide shaft relative the guide sleeve, the at
least one gripper arm connected to the guide shaft is at least
partly received in the guide sleeve by simultaneous radial
deformation. In this embodiment, the gripper arms of the claw
accordingly span outward like an umbrella when the guide shaft is
moved away from the actuating element relative the guide sleeve. It
is thereby effortlessly possible to form a releasable connection to
the stent which exhibits different respective cross-sections in the
uncompressed state with one and the same gripping mechanism.
[0055] On the other hand, this embodiment allows a precompressing
of the stent after the releasable connection to the stent having
been formed, and does so in that the guide shaft is displaced in
the direction of the actuating element relative the guide sleeve,
in consequence of which the umbrella-like stretched gripper arm
contracts radially. Since a retaining element preferably provided
on the distal end section of the stent is respectively connected to
the respective first end section of the gripper arm, a displacement
of the guide shaft relative the guide sleeve precompresses at least
the distal end section of the stent. The precompressing of the
distal end section of the stent is effected to a maximum diameter
predefined or predefinable by the internal diameter of the guide
sleeve. Accordingly, an internal diameter should be selected for
the guide sleeve which reflects a desired precompressing of the
distal end of the stent.
[0056] A preferred further embodiment of the device provides for
the gripping mechanism to comprise a spring mechanism which
interacts with the claw such that the claw can be spring-locked. It
is hereby particularly preferred for the spring mechanism to
comprise a spring, preferably a helical compression spring,
arranged in the retaining section of the actuating element such
that it pretensions the pushbutton of the actuating element against
the guide sleeve. As noted above, it is preferred for the
pushbutton to be designed as a manually-actuatable pushbutton
accommodated in the retaining section of the gripper mechanism and
movable relative the guide sleeve in the longitudinal direction of
the gripper mechanism.
[0057] In the latter embodiment in which the gripper mechanism
comprises a spring mechanism having a spring, in particular a
helical compression spring, it is preferable for the pre-tensioning
exerted by the spring on the pushbutton of the actuating element to
be selected such that without impacting the compressive force
exerted externally on the pushbutton, the claw--with the exception
of the fastening means provided at the first end section of the at
least one gripper arm--is accommodated completely within the guide
sleeve. This configuration accordingly allows the claw, the at
least one gripper arm of the gripper mechanism respectively, to
grasp the stent to be compressed, as well as the precompres sing of
the stent at least in certain areas.
[0058] In so doing, when the at least one gripper arm is driven out
from the guide sleeve, said at least one gripper arm spans evenly
in the radial direction. In order to achieve this, it is preferable
to select the spring's stroke to be shorter than the length of the
at least one gripper arm.
[0059] It is preferred for the compressing mechanism to comprise a
funnel-shaped area on at least one end. Providing a funnel-shaped
area simplifies the insertion of the stent to be compressed into
the interior of the compressing mechanism configured as a hollow
cylindrical body. The funnel-shaped area can further be accorded
the function of precompressing the stent when the stent is being
inserted into the compressing mechanism through the funnel-shaped
area. Accordingly, at least the end of the compressing mechanism
through which the stent to be compressed is inserted into said
compressing mechanism is configured as a funnel-shaped area.
[0060] Additionally to the at least one funnel-shaped area at an
end of the compressing mechanism, it is also preferred for the
compressing mechanism to additionally comprise a clamping area
aligned coaxially to the funnel-shaped area and connected to said
funnel-shaped area. The stent to be compressed is at least partly
accommodated in this clamping area after having passed through the
previously-mentioned funnel-shaped area. The actual compression of
the stent thereby occurs in the clamping area. Accordingly, the at
least one externally-manipulatable clamping jaw, which is movable
in the radial direction for adjusting the internal cross-sectional
diameter of the compressing mechanism, is accommodated in the
clamping area.
[0061] The clamping area of the compressing mechanism comprises a
mechanism for actuating the at least one clamping jaw which can
correspond to the mechanism of a clamping chuck. It is thus for
example conceivable to provide a clamping area which functions
according to the principle of traction.
[0062] With such a clamping area, the compressing mechanism can for
example exhibit a tensioning screw accommodated in the clamping
area which is rotatable about the longitudinal axis of the
compressing mechanism relative the at least one clamping jaw and
which interacts with the at least one clamping jaw such that upon a
rotation of the tensioning screw, the at least one clamping jaw is
displaced in the longitudinal direction of the compressing
mechanism relative to a clamping cone accommodated in the clamping
area. Such a mechanism enables the at least one clamping jaw to be
manipulated by rotating the tensioning screw such that it can move
in the radial direction relative to the longitudinal axis of the
compressing mechanism so as to enable the internal cross-sectional
diameter in the clamping area of the compressing mechanism to be
set to a predefinable value.
[0063] Alternatively hereto, however, it is also conceivable for
the compressing mechanism to comprise a tensioning screw
accommodated in the clamping area or another similar tensioning
element which is movable in the direction of the longitudinal axis
of the compressing mechanism relative the at least one clamping jaw
and interacts with the at least one clamping jaw such that upon the
tensioning screw moving relative the at least one clamping jaw, the
at least one clamping jaw is displaced in the longitudinal
direction of the compressing mechanism relative a clamping cone
accommodated in the clamping area. This type of mechanism likewise
enables the at least one clamping jaw to be manipulated by moving
the tensioning screw or tensioning element such that it can be
radially moved relative the longitudinal axis of the compressing
mechanism, thus allowing the internal cross-sectional diameter to
be set to a predefinable value in the clamping area of the
compressing mechanism.
[0064] The term "similar tensioning element" used herein means an
element which is movable in the direction of the longitudinal axis
of the compressing mechanism relative the at least one clamping jaw
and interacts with the at least one clamping jaw such that upon the
tensioning screw moving relative the at least one clamping jaw, the
at least one clamping jaw is displaced in the longitudinal
direction of the compressing mechanism relative a clamping cone
accommodated in the clamping area.
[0065] Specifically, in the latter embodiments of the clamping
area, the at least one clamping jaw is to interact with the
clamping cone such that upon a movement of the at least one
clamping jaw into the clamping cone, the at least one clamping jaw
is moved in the radial direction relative to the longitudinal axis
of the compressing mechanism, relative to the longitudinal axis of
the clamping area of the compressing mechanism respectively. As
already noted above, the movement of the at least one clamping jaw
into the clamping cone can be effected by rotating the tensioning
screw or moving the tensioning screw in the direction of the
longitudinal axis of the compressing mechanism. The clamping jaw
can be moved out of the clamping cone in the same way--by rotating
the tensioning screw in the opposite direction or by moving the
tensioning screw in the opposite direction in the direction of the
longitudinal axis of the compressing mechanism--as a consequence of
which, the at least one clamping jaw is moved outward perpendicular
to the radial direction away from the longitudinal axis of the
clamping area of the compressing mechanism.
[0066] Alternatively to the above-described realizations of the
clamping area, it is equally conceivable to configure the clamping
area of the compressing mechanism so as to be for example rotatable
about the longitudinal axis of the compressing mechanism relative
the at least one clamping jaw and interact with the at least one
clamping jaw such that the at least one clamping jaw moves in the
radial direction upon a rotation of the clamping area relative the
at least one clamping jaw.
[0067] In a preferred configuration of the latter embodiment of the
clamping area, it is conceivable to configure the clamping area as
a hollow cylinder exhibiting a substantially uniform external
diameter, whereby the wall thickness to the clamping area
configured as a hollow cylinder, however, varies along its
periphery so that the internal diameter of the clamping area
likewise varies. Conceivable here, for example, is for the inner
lateral surface of the clamping area configured as a hollow
cylinder to be of sinuous or sawtooth-like form in the unfolded
state. In the case of a clamping area designed as a hollow cylinder
and having a wall thickness which varies along its periphery, the
at least one clamping jaw of the compressing mechanism is to abut
against the inner lateral surface of the clamping area designed as
a hollow cylinder such that when the clamping area is rotated
relative the at least one clamping jaw, the at least one clamping
jaw is moved--in dependence on the wall thickness of the hollow
cylinder in the contact area with the at least one clamping jaw--in
the radial direction.
[0068] Alternatively to the above-described realizations of the
clamping area, it is equally conceivable for the clamping area to
be movable in the direction of the longitudinal axis of the
compressing mechanism relative the at least one clamping jaw and to
interact with the at least one clamping jaw such that upon the
clamping area moving relative the at least one clamping jaw, the at
least one clamping jaw is moved in the radial direction.
[0069] In one configuration of the latter embodiment of the
clamping area, it is preferable for the clamping area to be
configured as a hollow cylinder, the wall thickness of which varies
along its periphery, whereby the at least one clamping jaw abuts
the inner lateral surface of the clamping area configured as a
hollow cylinder such that upon the clamping area moving relative
the at least one clamping jaw, the at least one clamping jaw is
moved--in dependence on the wall thickness of the hollow cylinder
in the contact area with the at least one clamping jaw--in the
radial direction.
[0070] Particularly conceivable with the latter embodiments of the
clamping area is for the clamping area to be movable in the
direction of the longitudinal axis of the compressing mechanism
relative the funnel-shaped area.
[0071] In the cited possible configurations of the clamping area of
the compressing mechanism, the degree of compressive force exerted
radially by the at least one clamping jaw on the stent accommodated
in the compressing mechanism, in the clamping area of the
compressing mechanism respectively, can be adjusted by
appropriately selecting the configuration of the inner lateral
surface of the clamping area configured as a hollow cylinder.
Specifically, the greater degree to which the wall thickness along
the periphery of the clamping area configured as a hollow cylinder
increases, the larger the compressive force acting radially on the
outer surface of the stent accommodated in the clamping area of the
compressing mechanism by the at least one clamping jaw.
[0072] It is in principle preferred for the compressing mechanism
to exhibit a plurality of actuatable clamping jaws so as to enable
the most even distribution possible of the compressive force
exerted on the outer surface of the stent to be compressed
accommodated in the clamping area. If a hollow cylinder is used as
the clamping area, its wall thickness varying along its periphery,
wherein the respective clamping jaws abut the inner lateral surface
of the clamping area configured as a hollow cylinder such that upon
rotating the clamping area relative to the clamping jaws or upon
moving of the clamping area in the direction of the longitudinal
axis of the compressing mechanism relative to the clamping jaws,
the clamping jaws are moved radially--in dependence on the wall
thickness of the hollow cylinder in the contact area with the
respective clamping jaws--it is preferred for the inner lateral
surface of the clamping area configured as a hollow cylinder to be
configured such that the clamping jaws move uniformly in the radial
direction upon the rotating of the clamping area relative to the
clamping jaws or upon the moving of the clamping area in the
direction of the longitudinal axis of the compressing mechanism
relative to the clamping jaws. In this way, upon the compressing of
the stent in the clamping area of the compressing mechanism, this
allows the achieving of the stent being radially subjected to even
compressive forces from all sides in order to thus ensure an
uniformly even compressing of the stent without stress peaks.
[0073] In the latter cited embodiment of the clamping area in which
the clamping area is rotatable or movable relative the at least one
clamping jaw about the longitudinal axis of the compressing
mechanism and interacts with the at least one clamping jaw such
that upon a rotation or movement of the clamping area or upon
displacement in the direction of the longitudinal axis of the
compressing mechanism, the at least one clamping jaw is moved in
the radial direction, it is preferred for the clamping area to not
only be rotatable about the longitudinal axis of the compressing
mechanism relative the at least one clamping jaw or movable in the
direction of the longitudinal axis of the compressing mechanism
relative the at least one clamping jaw, but also relative the
funnel-shaped area of the compressing mechanism. So doing
simplifies the manipulating of the compressing mechanism since e.g.
the user of the compressing mechanism can hold the funnel-shaped
area of the compressing mechanism with his one hand while he
rotates the clamping area of the compressing mechanism about the
longitudinal axis of the compressing mechanism relative the
funnel-shaped area or moves it in the direction of the longitudinal
axis of the compressing mechanism relative the funnel-shaped area
with his other hand and thus manipulates the at least one clamping
jaw such that it moves in the radial direction and enables a
compressing of the stent accommodated in the clamping area of the
compressing mechanism.
[0074] The compressing mechanism and the gripping mechanism need
not be respectively configured as separate components. The
disclosure is however not limited to the previously-described
device for compressing a stent to which a prosthetic heart valve is
affixed as needed. Rather, another object of the present disclosure
also comprises a system for loading a stent, as needed with a
prosthetic heart valve affixed thereto, into a medical delivery
system, in particular into the catheter tip of a medical delivery
system. The system thereby comprises a device of the type as
described above consisting of a compressing mechanism and a
gripping mechanism. Additionally to the compressing mechanism, the
system further comprises a supplementary compressing mechanism.
[0075] As will be described below in detail making reference to the
accompanying figures, the compressing mechanism serves to compress
in particular the distal end section of the stent to be loaded into
the catheter tip of a medical delivery system and to load it into a
first sleeve-shaped element (receiving area) of the catheter tip.
The supplementary compressing mechanism is then employed in order
to compress in particular the proximal end section of the stent and
load said compressed proximal end section of the stent into a
further sleeve-shaped element (receiving area) of the catheter
tip.
[0076] Structurally and functionally, the supplementary compressing
mechanism can be con-figured similar to the compressing mechanism
employed in the device to compress a stent. Since the supplementary
compressing mechanism does not come into use until the distal end
section of the stent has already been compressed and loaded into
the first sleeve-shaped element of the catheter tip, it is thus in
principle conceivable to make use of the compressing mechanism
which was already used to compress the distal end section of the
stent as the supplementary compressing mechanism. It is however
also conceivable for the system to be provided with two compressing
mechanisms for loading a stent into a medical delivery system,
whereby one of the two compressing mechanisms is then used as the
supplementary compressing mechanism.
[0077] Thus, both the above-described device, with which a stent,
as needed with a prosthetic heart valve affixed thereto, can be
readily compressed, as well as the above-described system thereto,
provides for loading a stent, as needed with a prosthetic heart
valve affixed thereto, into a medical delivery system, in
particular into a catheter tip of a medical delivery system.
[0078] The present disclosure further relates to a method for
loading a stent, as needed with a prosthetic heart valve affixed
thereto, into a medical delivery system, in particular into the tip
of a catheter of a medical delivery system, whereby the
above-described device is used to compress the stent.
[0079] In the method for loading a stent into e.g. the catheter tip
of a medical delivery system, the gripping mechanism of the device
is first connected with the compressing mechanism such that the
gripping mechanism is at least partly accommodated within the
compressing mechanism. It is hereby preferred for at least one
guiding element to be designated for the gripping mechanism which
is configured to be complementary to at least one guiding element
designated for the compressing mechanism and which engages with the
guiding element of the compressing mechanism when the gripping
mechanism connects to the compressing mechanism.
[0080] After the gripping mechanism connects to the compressing
mechanism, the stent to be accommodated for example in the catheter
tip of the medical delivery system is grasped, and is done so in
that by actuating the actuating element of the gripping mechanism,
the claw of the gripping mechanism is accordingly manipulated so
that a releasable connection is formed between a distal end section
of the stent and the claw of the gripping mechanism. As already
detailed in conjunction with the device for compressing a stent, it
is preferred for a precompressing of at least the distal end
section of the stent to occur upon the grasping of the stent. This
can be realized when following the forming of a releasable
connection between the distal end section of the stent and the claw
of the gripping mechanism, the claw is moved toward the actuating
element relative the preferably provided guide sleeve by the
actuating of the actuating element.
[0081] A further precompressing of the stent occurs in a subsequent
method step in which the gripping mechanism with the claw, to which
the distal end section of the stent is releasably affixed, is moved
in the longitudinal direction relative the compressing mechanism
such that the stent is at least partly accommodated within the
compressing mechanism. By the gripping mechanism moving in the
longitudinal direction of the compressing mechanism relative said
compressing mechanism, the stent releasably connected to the claw
of the gripping mechanism is thus introduced into the interior of
the compressing mechanism. It is hereby advantageous for the
compressing mechanism to exhibit the previously-described
funnel-shaped area at the insertion end of the compressing
mechanism in order to facilitate the insertion of the stent into
the compressing mechanism, the clamping area of the compressing
mechanism respectively.
[0082] After the stent, as needed with a prosthetic heart valve
affixed thereto, has been at least partly accommodated inside the
compressing mechanism, the connection between the stent and the
gripping mechanism is disengaged. This ensues by a re-actuating of
the actuating element of the gripping mechanism so that the claw of
the gripping mechanism can be manipulated such that it moves
relative to the gripping mechanism and the connection between the
distal end section of the stent and the claw is disengaged.
[0083] After the gripping mechanism releases from the stent, the
actual compressing of at least the distal end section of the stent
occurs in the clamping area of the compressing mechanism. To this
end, the at least one clamping jaw of the compressing mechanism is
manipulated such that the at least one clamping jaw moves radially
relative the compressing mechanism perpendicular to the direction
of the longitudinal axis of the compressing mechanism. As
previously described in conjunction with the device, the
manipulating of the at least one clamping jaw can ensue for example
by the corresponding actuating of a clamping chuck-like mechanism
of the compressing mechanism which effects a movement of the at
least one clamping jaw in the direction of the longitudinal axis of
the compressing mechanism.
[0084] After at least the distal end section of the stent being
thus so compressed in defined manner in the compressing mechanism
such that the diameter of at least the distal end section of the
stent exhibits a predefinable value, the compressed distal end
section of the stent is introduced into a first sleeve-shaped
element (receiving area) of the catheter tip of the medical
delivery system.
[0085] The method for loading a stent into the catheter tip of a
medical delivery system preferably provides for the compressing
mechanism to introduce at least the distal end section of the stent
into at least one area of the catheter tip of the medical delivery
system prior to the manipulation of the at least one clamping jaw
during the actual compressing. Only after the compressing mechanism
with the stent accommodated therein is inserted into the tip of the
catheter of the medical delivery system does the actual compressing
of at least the distal end section of the stent occur by the
appropriate manipulating of the at least one clamping jaw of the
compression mechanism. This occurs because the diameter of the
compressed distal end section of the stent is normally smaller than
the external diameter of the catheter tip of the medical delivery
system such that the actual compressing of the distal end section
of the stent is to occur in direct proximity to the first
sleeve-shaped element of the catheter tip.
[0086] In order to achieve that also the proximal end section of
the stent can be accommodated in compressed manner in the catheter
tip of the medical delivery system, a preferred embodiment of the
method makes use of the above-noted supplementary compressing
mechanism. Specifically, it is thereby provided that at least one
area of the catheter tip of the medical delivery system is inserted
through the supplementary compressing mechanism configured as a
hollow cylindrical body such that the supplementary compressing
mechanism abuts against the (not yet fully compressed) proximal end
section of the stent at least partly accommodated within the
compressing mechanism.
[0087] Before the supplementary compressing mechanism is used to
compress the proximal end section of the stent, however, it is
preferable to remove the compressing mechanism, with which the
distal end section of the stent is compressed, from the catheter
tip of the medical delivery system. This should occur after the
compressed distal end section of the stent has been loaded into the
first sleeve-shaped element of the catheter tip.
[0088] To remove the compressing mechanism, the at least one
clamping jaw of the compressing mechanism is manipulated such that
the at least one clamping jaw is moved radially outward relative
the compressing mechanism away from the longitudinal axis of the
compressing mechanism. Because the distal end section of the stent
is already loaded into the first sleeve-shaped element of the
catheter tip, the distal end section of the stent remains in its
compressed form although the at least one clamping jaw of the
compressing mechanism now no longer exerts a radially-acting
compressive force on the stent.
[0089] After the at least one clamping jaw of the compressing
mechanism being manipulated so as to no longer exert any radial
compressive force on the outer surface of the stent, the
compressing mechanism can be removed from the catheter tip of the
medical delivery system.
[0090] The supplementary compressing mechanism can thereafter be
used to compress the not yet fully compressed proximal end section
of the stent such that the proximal end section of the stent can be
loaded into a further sleeve-shaped element of the catheter
tip.
[0091] To this end, the supplementary compressing mechanism is
moved toward the proximal end section of the stent such that at
least the proximal end section of the stent is at least partly
received within the supplementary compressing mechanism configured
as a hollow cylindrical body. In this position, the supplementary
compressing mechanism can effect a compressing of at least the
proximal end section of the stent.
[0092] In detail, at least the proximal end section of the stent is
compressed in that the at least one clamping jaw of the
supplementary compressing mechanism is manipulated such that the at
least one clamping jaw is radially moved relative the supplementary
compressing mechanism perpendicular to the direction of the
longitudinal axis of said supplementary compressing mechanism. It
is readily apparent that the degree of compression of the proximal
end section of the stent is selectable at will, and this is done by
correspondingly selecting the extent of manipulation for the at
least one clamping jaw of the supplementary compressing mechanism.
The same also applies figuratively to the compressing of the distal
end section of the stent.
[0093] After the supplementary compressing mechanism compressing
the proximal end section of the stent, the compressed proximal end
section of the stent is introduced into at least one second
sleeve-shaped element (receiving area) of the catheter tip of the
medical delivery system.
[0094] The supplementary compressing mechanism can thereafter also
be removed from the catheter tip of the medical delivery system.
This ensues by correspondingly manipulating the at least one
clamping jaw of the supplementary compressing mechanism such that
the at least one clamping jaw is radially moved outward relative
the supplementary compressing mechanism perpendicular to the radial
direction of the longitudinal axis of said supplementary
compressing mechanism.
[0095] The following will make reference to the accompanying
drawings in describing examples of the disclosed solution.
[0096] Shown are:
[0097] FIG. 1 a perspective view of an exemplary embodiment of the
disclosed device for compressing a stent, wherein the device is
shown in its initial state;
[0098] FIG. 2 a perspective view of the device for compressing a
stent in a stent-grasping state;
[0099] FIG. 3 a perspective view of the initial state of the
gripping mechanism used in the exemplary embodiment of the device
for compressing a stent;
[0100] FIG. 4 a perspective view of the gripping mechanism used in
the exemplary embodiment of the device in a stent-grasping
state;
[0101] FIG. 5 a perspective view of the gripping mechanism used in
the exemplary embodiment of the device for compressing a stent
without a guide sleeve;
[0102] FIG. 6 a perspective view of the compressing mechanism used
in the exemplary embodiment of the device with a stent at least
partly accommodated therein prior to the actual compressing of the
stent in the compressing mechanism;
[0103] FIG. 7 a perspective view of the compressing mechanism used
in the exemplary embodiment of the device for compressing a stent
with a stent at least partly accommodated therein after the
compressing of the stent in the compressing mechanism;
[0104] FIG. 8 a top plan view of the compressing mechanism shown in
FIG. 7;
[0105] FIG. 9a a perspective view of the clamping mechanism used in
the clamping area of the compressing mechanism of the exemplary
embodiment of the device for compressing a stent;
[0106] FIG. 9b a perspective view from below into the funnel-shaped
area of the compressing mechanism shown in FIG. 6 without a
stent;
[0107] FIG. 10a-f perspective views of the exemplary embodiment of
the device illustrating the functioning during the compression of a
stent;
[0108] FIG. 11a-c perspective views of the exemplary embodiment of
the system illustrating the loading of a stent into the catheter
tip of a medical delivery system;
[0109] FIG. 12 a side view of an exemplary embodiment of a catheter
tip of a medical delivery system for transapically introducing a
stent; and
[0110] FIG. 13 a side view of an exemplary embodiment of a catheter
tip of a medical delivery system for transfemorally/transarterially
introducing a stent.
[0111] Reference will be made in the following to the accompanying
drawings in describing an exemplary embodiment of the device 1 for
compressing a stent 100. FIG. 1 shows a perspective view of the
exemplary embodiment of the device 1 in its initial state; i.e. a
state in which the device 1 is received from the factory.
[0112] The device 1 substantially comprises a compressing mechanism
10 in the form of a hollow cylindrical body, within which a stent,
not shown in FIG. 1, can be at least partly received. Particular
reference will be made in the following to the representations
shown in FIGS. 6 to 9 in describing the structure and the
functioning of the compressing mechanism 10 in greater detail.
[0113] The exemplary embodiment of device 1 depicted in FIG. 1
further comprises a gripping mechanism 20 which in the initial
state of device 1 is at least partly accommodated within the
compressing mechanism 10 configured as a hollow cylinder.
Particular reference will be made in the following to the
representations shown in FIGS. 3 to 5 in describing the structure
and the functioning of the gripping mechanism 20 in greater
detail.
[0114] As will subsequently be described in detail in the
following, the compressing mechanism 10 serves the device 1 with
respect to the exerting of a compressive force acting in the radial
direction (relative the longitudinal direction of said compressing
mechanism 10) on a stent accommodated in the compressing mechanism
10 in defined manner so as to reduce the cross-section of the stent
to a predefinable value. In doing so, it is first required for the
stent to be compressed to be at least partly inserted into the
compressing mechanism 10 configured as a hollow cylinder. This task
is assumed by the gripping mechanism 20 of the device 1 which--as
will be described below in greater detail--is designed so as to
create a releasable connection with the stent to be compressed. In
particular, the gripping mechanism 20 serves to create a releasable
connection with the distal end section of the stent to be
compressed and thereafter introduce the stent into the compressing
mechanism 10 configured as a hollow cylinder.
[0115] To this end, the gripping mechanism 20 is displaceably
receivable within the compressing mechanism 10 configured as a
hollow cylinder in the longitudinal direction relative said
compressing mechanism 10. The gripping mechanism 20 further
comprises an actuating element 21 provided with a claw 22 for
grasping the stent to be compressed.
[0116] In the exemplary embodiment depicted in the drawings, the
actuating element 21 of the gripping mechanism 20 exhibits a
manually-actuatable pushbutton 26 accommodated in a retaining
section 25 and displaceable in the longitudinal direction of the
gripping mechanism 20 relative a guide sleeve 23.
[0117] To be seen in conjunction hereto from the representation
provided in FIG. 2 is that upon the actuating of actuating element
21; i.e. upon an external compressive force being exerted on the
manually-actuatable pushbutton 26, the pushbutton 26 is moved in
the longitudinal direction of the gripping mechanism 20 relative
retaining section 25. The pushbutton 26 is directly connected to
the claw 22 of the gripping mechanism 20 so that upon the
pushbutton 26 being actuated, actuating element 21 moves the claw
22 in the longitudinal direction of the gripping mechanism 20
relative the guide sleeve 23.
[0118] By actuating element 21 being pressed by the pushbutton
26--as shown in FIG. 2--the claw 22 of gripping mechanism 20 is
thus at least partly moved out of the guide sleeve 23. The distance
by which the claw 22 is moved out of the guide sleeve 23 depends on
the actuated travel of the pushbutton 26.
[0119] In the exemplary embodiment of device 1, the claw 22
exhibits three gripper arms 27.1, 27.2, 27.3, whereby each gripper
arm 27.1, 27.2, 27.3 comprises respective fastening means 28.1,
28.2 at its first end section. These fastening means 28.1, 28.2
serve to form a releasable connection with a stent to be
compressed, as will be subsequently described in detail referencing
the representations provided in FIGS. 10a to 10f.
[0120] The fastening means 28.1, 28.2 respectively provided on the
first end sections of the gripper arms 27.1, 27.2, 27.3 are
designed in complementary fashion to a retaining section formed on
the stent to be compressed so that the fastening means 28.1, 28.2
are designed to releasably engage with a retaining section of the
stent to be compressed. In detail, and as can particularly be seen
from the representations provided in FIGS. 1 to 5, the respective
fastening means 28.1, 28.2 provided on the respective gripper arms
27.1, 27.2, 27.3 in the exemplary embodiment of the device 1
exhibit a projecting element 28.1 which can be brought into
releasable engagement with a correspondingly
complementary-configured retaining grommet of a stent to be
compressed. Additionally to this projecting element 28.1, recesses
28.2 particularly in the form of a preferably oblong grommet are
formed in the respective first end sections of the gripper arms
27.1, 27.2, 27.3. Each of said recesses 28.2 can be brought into
releasable engagement with a correspondingly
complementary-configured projecting retaining element of a stent to
be compressed.
[0121] The gripping mechanism 20 used in the exemplary embodiment
of the device 1 will be described in greater detail in the
following referencing the representations provided in FIGS. 3 to 5.
Specifically, FIG. 3 shows a perspective view of the gripping
mechanism 20 in its initial state; i.e. in a state in which the
pushbutton 26 of actuating element 21 has not been actuated.
[0122] As already described in conjunction with the FIG. 1
representation, the claw 22 with gripper arms 27.1, 27.2, 27.3 is
accommodated so far into the guide sleeve 23 in the initial state
of the gripping mechanism 20 that only the fastening means 28.1,
28.2 provided on the first end sections of the gripper arms 27.1,
27.2, 27.3 protrude from the open ends of the guide sleeve 23. The
remaining parts of the gripper arms 27.1, 27.2, 27.3, the claw 22
respectively, are accommodated within the guide sleeve 23
configured as a hollow cylindrical body.
[0123] FIG. 4 shows the gripping mechanism 20 depicted in FIG. 3 in
a state prepared to grasp a not-explicitly shown stent.
Specifically, in the state of the gripping mechanism 20 shown in
FIG. 4, the pushbutton 26 of actuating element 21 has been actuated
such that the claw 22 with the gripper arms 27.1, 27.2, 27.3 will
be displaced in the longitudinal direction of the gripping
mechanism 20 relative the guide sleeve 23 and the retaining section
25 to which the guide sleeve 23 is fixedly connected such that not
only the respective fastening means 28.1, 28.2 of gripper arms
27.1, 27.2, 27.3 protrude out of the open end of the guide sleeve
23, but also the actual gripper arms 27.1, 27.2, 27.3 themselves.
When the gripper arms 27.1, 27.2, 27.3 are extended out of the end
of the guide sleeve 23, they radially span outward like an
umbrella--as can in particular be seen in the FIG. 4
representation--such that the effective gripping area of claw 22,
gripper arms 27.1, 27.2, 27.3 respectively, is increased.
[0124] It is preferred for the maximum gripping area of claw 22,
gripper arms 27.1, 27.2, 27.3 respectively, to be such so as to be
able to grasp stents up to an external diameter of 30.0 mm.
However, it is of course also possible to dimension the gripping
area of claw 22 for stents having larger external diameters.
[0125] As will be described in greater detail referencing the
representations provided in FIGS. 10a-f, the gripping mechanism 20
already effects a precompressing of a stent grasped by the claw 22.
If the gripping mechanism 20 namely transforms back to its state as
shown in FIG. 3 from that as shown in FIG. 4 by the releasing of
pushbutton 26 of actuating element 21, the gripper arms 27.1, 27.2,
27.3 will pull claw 22 back into the guide sleeve 23 configured as
a hollow cylinder, which will have the consequence of the stent
releasably connected via the fastening means 28.1, 28.2 provided at
the first end sections of the gripper arms 27.1, 27.2, 27.3 also
being moved along therewith in the radial direction. In this way,
at least the area of the stent to be compressed at which the
gripper arms 27.1, 27.2, 27.3 of the gripping mechanism 20 are
connected can be precompressed. The extent of precompression
effected via the gripping mechanism 20 is dependent on the internal
diameter of the guide sleeve 23 configured as a hollow
cylinder.
[0126] FIG. 5 shows a perspective view of a gripping mechanism 20
used in the exemplary embodiment of the device 1 without guide
sleeve 23. It is especially to be seen from the representation of
FIG. 5 that the claw 22 of gripping mechanism 20 comprises a guide
shaft 29 additionally to gripper arms 27.1, 27.2, 27.3 which can,
for example, be of substantially cylindrical design. The first end
29a of guide shaft 29 is connected to the respective second end
sections of gripper arms 27.1, 27.2, 27.3, whereby the second end
29b of guide shaft 29 is connected to the actuating element 21 of
gripper mechanism 20 and specifically to the pushbutton 26 of the
actuating element 21.
[0127] It is of course also conceivable to dispense with the guide
shaft 29 and directly connect the second end sections of the
respective gripper arms 27.1, 27.2, 27.3 to the actuating element
21 of the gripping mechanism 20, respectively to the pushbutton 26
of said actuating element 21. However, the guide shaft 29 enables
the claw 22 to be moved with as little resistance as possible
relative the guide sleeve 23 upon actuating element 21 being
actuated.
[0128] In order to prevent the possible canting or wedging of the
guide shaft 29 in its movement relative to the guide sleeve 23 upon
the actuating element 21 being actuated, the exemplary embodiment
of device 1 provides guiding means 30 to guide the guide shaft 29
within the guide sleeve 23 when the guide shaft 29--as depicted for
example in FIGS. 3 and 4--is accommodated within the guide sleeve
such that the guide shaft 29 together with the gripper arms 27.1,
27.2, 27.3 connected to said guide shaft 29 can be displaced
relative to guide sleeve 23.
[0129] To be noted from the FIG. 5 representation is that the guide
means 30 are designed as protruding guiding surfaces provided at
the first end section 29a of guide shaft 29. However, it is of
course also conceivable to dispose guiding means 30 in another area
of guide shaft 29.
[0130] As can be noted from the perspective representation
according to FIG. 5, the gripping mechanism 20 further comprises a
spring mechanism in the form of a helical compression spring 31
accommodated in the retaining section 25 and pretensioning the
pushbutton 26 of actuating element 21 against the guide sleeve 23
via the underface 32 of the retaining section 25 in the assembled
state of gripping mechanism 20 (cf. FIGS. 3 and 4). It is thereby
specifically provided for the guide sleeve 23 to be fixedly
connected to the underface 32 of retaining section 25.
[0131] Providing the spring mechanism in retaining section 25 of
actuating element 21 as realized by means of the spring 31 thus
ensures that the gripping mechanism 20 will be held in the initial
state as shown in FIG. 3 in the assembled state of said gripping
mechanism 20 (cf. FIGS. 3 and 4), as long as no opposing force
exceeding the pretensioning force exerted by the spring 31 is
exerted on pushbutton 26 of actuating element 21. In the gripping
mechanism 20 used in the exemplary embodiment of the device 1, the
guide shaft 29 is namely connected to the claw 22 via the underside
of pushbutton 26 such that force exerted on the pushbutton 26 via
spring 31 is transmitted from the pushbutton 26 to the guide shaft
29, claw 22 respectively.
[0132] Selecting the appropriate spring constant or stiffness to
spring 31 of the spring mechanism enables spring 31 to set the
pretensioning exerted on pushbutton 26 of actuating element 21. To
be factored in hereby is that the pretensioning is to be selected
such that without impacting any compressive force exerted
externally on the pushbutton 26; i.e. in the initial state of the
gripping mechanism 20, the claw 22--with the exception of the
fastening means 28.1, 28.2 provided at the first end section of
gripper arms 27.1, 27.2, 27.3--is completely accommodated within
guide sleeve 23. This should preferably also be the case when the
claw 22 grasps a stent to be compressed via the fastening means
28.1, 28.2 of gripper arms 27.1, 27.2, 27.3.
[0133] As already indicated with reference to the FIG. 1 and FIG. 2
representation, the gripping mechanism 20 is at least partly
accommodated within the compressing mechanism 10 so as to be
displaceable in the longitudinal direction relative the compressing
mechanism 10. In order to guide the relative motion of the gripping
mechanism 20 accommodated in the compressing mechanism 10, and in
particular to facilitate the receiving of the gripping mechanism 20
within the compressing mechanism 10, the guide sleeve 23 comprises
guiding elements 24 which are configured as guide rails in the
exemplary embodiment depicted in the drawings. These guiding
elements 24 configured as guide rails extend in the longitudinal
direction of the guide sleeve 23 and are configured complementary
to the guiding elements 12 allocated to the compressing mechanism
10. The guiding elements 12 allocated to the compressing mechanism
10 can be noted from the FIG. 9b representation which shows a
perspective view from below into the funnel-shaped area 13 of the
compressing mechanism 10 shown in FIG. 6 without a stent.
[0134] As can be seen for example in the representation of FIG. 9b,
the guiding elements 12 allocated to compressing mechanism 10 are
configured as guiding grooves extending in the longitudinal
direction of compressing mechanism 10.
[0135] It can in particular be noted from the FIG. 5 representation
that the gripper arms 27.1, 27.2, 27.3, and preferably also the
connecting area 33 between the end sections of the gripper arms
27.1, 27.2, 27.3 and the first end section 29a of guide shaft 29,
are configured to be elastically deformable such that upon a
displacement of the guide shaft 29 relative the guide sleeve 23,
the gripper arms 27.1, 27.2, 27.3 connected to the guide shaft 29
can be at least partly accommodated in the guide sleeve 23 under
simultaneous radial elastic deformation.
[0136] The compressing mechanism 10 used in the exemplary
embodiment of the device 1 will be described in the following
making reference to the FIG. 6 to FIG. 9b representations.
Specifically, FIG. 6 shows a perspective view of the compressing
mechanism 10 used in the exemplary embodiment of the device 1,
within which a stent 100 is at least partly accommodated prior to
its actual compressing.
[0137] It is hereby noted that only for the sake of clarity in the
drawings, the stent 100 is depicted schematically as a cylindrical
body without any further rendering of the stent's structural
details. The device 1 is suited for cylindrical stents with which
the gripping mechanism 20 can create a releasable connection in
order to introduce the stent 100 into the compressing mechanism 10.
In particular, the device is suited to compress a stent 100 which
comprises retaining elements on its distal end section 101 with
which the gripping mechanism 20 can form a releasable
connection.
[0138] The device 1 is suited to compress an expandable, and in
particular self-expandable stent 100. The stent 100 assumes--while
it is accommodated in the catheter tip of the medical delivery
system--a first predefinable shape. However, outside of the
catheter tip, in the implanted state respectively, the stent 100 is
in a second predefinable shape. The first shape of the stent 100
thereby corresponds to the folded state while in the expanded
state, the stent 100 is in its second shape.
[0139] For example, the device 1 is suitable for compressing a
stent 100 as described for example in European patent application
No. 07 110 318 or European patent application No. 08 151 963. A
preferred realization of device 1 accordingly designed to compress
a stent 100 thus comprises the following: [0140] a first retaining
section, proximal end section respectively, to which a prosthetic
heart valve can be affixed; [0141] an oppositely-arranged second
retaining section, distal end section respectively, having at least
one retaining element, for example in the form of a retaining
grommet or in the form of a retaining head, whereby the at least
one retaining element of the stent can be brought into releasable
engagement with a stent holder of a delivery system's catheter tip;
[0142] at least one retaining holder to which a prosthetic heart
valve can be affixed; and [0143] at least one and preferably three
positioning holders which are designed to engage in the pockets of
the native heart valve in the implanted state of the stent in order
to thus enable the self-positioning of the stent in the aorta of
the patient.
[0144] The use of device 1 is however in no way limited to this
type of stent.
[0145] As can be seen from the FIG. 6 representation, the
compressing mechanism 10 exhibits a funnel-shaped area 13 at one
end. A clamping area 14, aligned coaxially and connected to the
funnel-shaped area 13, adjoins said funnel-shaped area 13. The
clamping area 14 of the compressing mechanism 10 serves in exerting
a radially-acting compressive force in defined manner on a stent
100 accommodated in the compressing mechanism 10 such that the
cross-section of the stent 100 can be reduced to a predefinable
value. To this end, the compressing mechanism 10 exhibits clamping
jaws 11.1-11.6, individually accommodated in the clamping area 14.
These clamping jaws 11.1-11.6 can be radially moved to adjust the
internal cross-sectional diameter of the compressing mechanism 10
in clamping area 14.
[0146] As will be described in greater detail below referencing the
FIG. 9a representation, a suitable clamping mechanism is used for
this purpose which can be externally manipulated in order to move
the clamping jaws 11.1-11.6 in the radial direction.
[0147] In detail, the exemplary embodiment of the device 1 provides
for the clamping area 14 to be rotatable about the longitudinal
axis of the compressing mechanism 10 relative the funnel-shaped
area 13. On the other hand, the clamping jaws 11.1-11.6 provided in
clamping area 14 are connected to the funnel-shaped area 13, as can
be seen in the FIG. 9a representation. Accordingly, the clamping
area 14 is also configured to be rotatable relative the clamping
jaws 11.1-11.6.
[0148] It can be noted from the top plan view of compressing
mechanism 10 shown in FIG. 8 that the clamping area 14 is
configured as a body similar to a hollow cylinder, whereby the wall
thickness of the hollow cylinder-like body varies along its
periphery at least in one area of the clamping area 14. The
individual clamping jaws 11.1-11.6 are thereby positioned on the
internal lateral surfaces of clamping area 14 such that by a
rotating of clamping area 14 relative clamping jaws 11.1-11.6, the
respective clamping jaws 11.1-11.6 will be moved--in dependence on
the wall thickness of the hollow cylinder-like body in the
respective contact areas with clamping jaws 11.1-11.6--in the
radial direction.
[0149] The functioning of the compressing mechanism 10 used in the
exemplary embodiment of device 1 will be described in greater
detail in the following referencing the representations provided in
FIGS. 6 and 7. Specifically, FIG. 6 shows the compressing mechanism
10 in a perspective view, whereby the (only schematically-depicted)
stent 100 is at least partly accommodated in the clamping area 14
of compressing mechanism 10. FIG. 6 shows the stent 100 in a state
in which no compression has yet been effected by the clamping area
14 of the compressing mechanism 10.
[0150] In detail, it can be noted from the FIG. 6 representation
that the respective clamping jaws 11.1-11.6 are only provided at
the upper area of clamping area 14; i.e. in the area of clamping
area 14 situated opposite the funnel-shaped area 13 of compressing
mechanism 10. By providing the clamping jaws 11.1-11.6 at the upper
area of clamping area 14, the entire stent 100 as a whole is not
compressed, but instead only the end section of the stent 100
positioned at the height of the clamping jaws 11.1-11.6 in the
accommodated state as shown in FIG. 6.
[0151] The individual clamping jaws 11.1-11.6 are preferably
configured such that they exhibit a relatively large contact
surface 15 over which the radial compressive force from clamping
jaws 11.1-11.6 is exerted on the outer surface of the stent 100 in
the compressing of stent 100.
[0152] If the clamping area 14--starting from the state as shown in
FIG. 6--is now rotated relative the funnel-shaped area 13 and thus
relative the clamping jaws 11.1-11.6 in the direction of the arrow,
the individual clamping jaws 11.1-11.6 will be radially pressed in
the direction of the longitudinal axis of the compressing mechanism
10. This is to be attributed to the clamping jaws 11.1-11.6 being
guided along the inner lateral surfaces of clamping area 14 by the
rotating of clamping area 14 relative clamping jaws 11.1-11.6.
[0153] In detail, the compressing mechanism 100 employed in the
exemplary embodiment of the device 1 provides a respective grooved
guide 16.1-16.6 for each clamping jaw 11.1-11.6, whereby the
respective transfer functions of grooved guides 16.1-16.6 are
determined by the course taken by the respective guiding surfaces
17.1-17.6 provided for clamping jaws 11.1-11.6. The respective
clamping jaws 11.1 to 11.6 are forcibly driven along guiding
surfaces 17.1-17.6 of the respective grooved guides 16.1-16.6 upon
clamping area 14 being rotated relative to the clamping jaws
11.1-11.6.
[0154] The respective grooved guides 16.1-16.6 are thereby selected
such that a transfer function is realized upon clamping area 14
being rotated relative the clamping jaws 11.1-11.6 which effects a
movement of clamping jaws 11.1-11.6 in the radial direction.
[0155] FIG. 7 shows the compressing mechanism 10 depicted in FIG. 6
in a state in which the respective clamping jaws 11.1-11.6 are
positioned in the area of the corresponding grooved guides
16.1-16.6 in which the clamping jaws 11.1-11.6 are moved in the
radial direction on the longitudinal axis of compressing mechanism
100 by the rotating of clamping area 14 relative the clamping jaws
11.1-11.6. As can be noted in particular from FIG. 6, the guide
webs 18.1-18.6 of the respective clamping jaws 11.1-11.6, guided
along the guiding surfaces 17.1-17.6 upon the rotating of clamping
area 14 relative clamping jaws 11.1-11.6., engage in the
corresponding stops 19.1-19.6. The engaging of guide webs 18.1-18.6
in the respective stops 19.1-19.6 completes the radial movement of
clamping jaws 11.1-11.6 in the direction of the longitudinal axis
of compressing mechanism 10.
[0156] The compressing mechanism 10 depicted in the drawings makes
use of a total of six clamping jaws 11.1-11.6 to transfer the
compressive force acting radially on the lateral surface of stent
100 as evenly as possible during the compressing of stent 100.
[0157] The contact surfaces 15.1-15.6 of clamping jaws 11.1-11.6
are moreover designed to encompass large areas so as to avoid
stress peaks during the transfer of the radially-acting compressive
force so that unnecessary stressing and possibly damaging of the
stent 100 can be prevented during its compression.
[0158] The present disclosure is not limited to the clamping
mechanism as described above with reference to the representations
of FIGS. 6 to 9a/9b. It is also conceivable, for example, to use a
clamping chuck-like mechanism in which a tensioning screw is
provided in the clamping area 14 which is rotatable or movable
about the longitudinal axis of the compressing mechanism 10
relative the clamping jaws 11.1-11.6 and which interacts with the
clamping jaws 11.1-11.6 such that upon the tensioning screw being
rotated or moved, the clamping jaws 11.1-11.6 are displaced in the
longitudinal direction of the compressing mechanism 10 relative a
clamping cone accommodated in clamping area 14. By the clamping
jaws 11.1-11.6 moving into the clamping cone, the clamping jaws
11.1-11.6 are thereby moved in the radial direction.
[0159] A preferred use of the above-described exemplary embodiment
of device 1 will be described in the following referencing the
representations shown in FIGS. 10a to 10f. It will specifically be
described how the device 1 provides a reliable way for a stent 100
to be transformed from its expanded state into a compressed
state.
[0160] FIG. 10a depicts the device 1 in its initial state as
described above referencing the representations shown in FIG. 1 to
FIG. 9b. In order to be able to compress the stent from its given
expanded state with the device 1 shown in FIG. 10a in a defined
manner pursuant a predefinable sequence of events, the actuating
element 21 of gripping mechanism 20 is first actuated by pressing
pushbutton 26. As already described especially in conjunction with
FIGS. 3 to 5, the claw 22 of gripping mechanism 20 is at least
partly driven out of the guide sleeve 23 upon the actuating of
actuating element 21 so that the gripper arms 27.1, 27.2, 27.3 span
outward like an umbrella (cf. FIG. 10b). Upon the actuating of
actuating element 21, the gripping area of claw 22 amounts to e.g.
30 mm so as to accommodate stents up to an external diameter of 30
mm.
[0161] FIG. 10c shows how a stent 100 to be compressed can be
grasped by the claw 22 extending partly from the guide sleeve 23.
It is hereby to be assumed that the fastening means 28.1, 28.2
provided at the end section of gripper arms 27.1, 27.2, 27.3 are
releasably connected to a retaining section provided at the distal
end section 101 of the stent 100 to be compressed. It is hereby
conceivable, for example, for the fastening means 28.1, 28.2 of
gripper arms 27.1, 27.2, 27.3 to form a releasable engagement with
corresponding retaining elements of the stent 100 to be
compressed.
[0162] After the claw 22 is connected to the distal end section 101
of stent 100 via the fastening means 28.1, 28.2 of gripper arms
27.1, 27.2, 27.3, the pushbutton 26 of actuating element 21 is
released--as shown in FIG. 10d--so that external compressive force
is no longer exerted on pushbutton 26. Due to the pretensioning
exerted on pushbutton 26 by the spring 31 of the spring mechanism,
the claw 22 together with the stent 100 affixed to the claw 22, to
the respective gripper arms 27.1, 27.2, 27.3 respectively, is
pulled toward the funnel-shaped area 13 of the compressing
mechanism 10 when pushbutton 26 is released. Since the gripper arms
27.1, 27.2, 27.3 are radially pulled in together with this
movement, a precompressing of at least the distal end section 101
of stent 10 already occurs in the state as depicted in FIG.
10d.
[0163] Subsequently, as shown in FIG. 10e, the gripping mechanism
20 together with the stent 100 connected to said gripping mechanism
20 is moved relative the compressing mechanism 10 such that the
stent 100 is at least partly accommodated inside the compressing
mechanism 10. Specifically, the distal end section 101 of the stent
100 may in an exemplary arrangement protrude from the upper opening
of the compressing mechanism 10 by about 10.0 mm.
[0164] After the stent 100 is received in the compressing mechanism
10, the connection between the claw 22 of gripping mechanism 20 and
the distal end section 101 of the stent 100 is again disengaged--as
can be seen in the representation according to FIG. 10f. To this
end, the pushbutton 26 of the actuating element 21 is pressed so
that the claw 22 with the gripper arms 27.1, 27.2, 27.3 is driven
at least partly out of the guide sleeve 23 and the gripper arms
27.1, 27.2, 27.3 spread out radially, in consequence of which the
connection to the distal end section 101 of the stent 100 is
disengaged.
[0165] The stent 100 thus inserted into the compressing mechanism
10 can now be compressed to the desired diameter, and in fact done
so by the clamping area 14 being rotated relative to the
funnel-shaped area 13 such that the clamping jaws 11.1-11.6 exert a
radial compressive force on at least one area of the lateral
surface of the stent 100 accommodated in the compressing mechanism
10. How the stent 100 can specifically be compressed within
compressing mechanism 10 has already described with reference to
FIGS. 6 to 9a.
[0166] The functioning of an exemplary embodiment of the system for
loading a stent 100 into the catheter tip 105 of a medical delivery
system will be described in the following referencing the FIG. 11a
to FIG. 11c representations. In the exemplary embodiment depicted
in FIGS. 11a-11c, a stent 100 is loaded in the catheter tip 105 of
a medical delivery system designed for a transapical approach,
although the system for loading a stent is of course also designed
for a transfemoral or transarterial delivery system. In a medical
delivery system designed for a transapical approach, the stent 100,
as needed with the prosthetic heart valve affixed thereto, is
advanced from the apex of the heart to the implantation site in the
heart. In a medical delivery system designed for a transarterial or
transfemoral approach, the stent 100, as needed with the prosthetic
heart valve likewise affixed thereto, is advanced to the
implantation site through the aorta of a patient to be treated.
[0167] The embodiment of the system for loading a stent 100 into
the catheter tip 105 of a medical delivery system as depicted in
FIGS. 11a to 11c comprises a device 1 as previously described when
referencing the representations provided in FIGS. 1 to 10. A device
1 is thus used to compress a stent 100, whereby the device 1
comprises a compressing mechanism 10 as well as a gripping
mechanism 20.
[0168] To load the stent 100 into the catheter tip 105 of the
medical delivery system, the gripping mechanism 20 first inserts
the stent 100 into the compressing mechanism 10, as has been
described in detail referencing FIGS. 10a-10f.
[0169] Prior to the compressing mechanism 10 effecting the
compressing of the stent 100, the catheter tip 105 of the medical
delivery system is first introduced through the compressing
mechanism 10 and then the precompressed stent 100 in the
compressing mechanism 10. Not until that point is the stent 100
accommodated in the compressing mechanism 10 actually compressed by
manipulating the clamping jaws 11.1-11.6, as described above
referencing FIGS. 6 to 9b.
[0170] As depicted in FIG. 11b, the clamping area 14 of the
compressing mechanism 10 is displaced relative the funnel-shaped
area 13--after the catheter tip 105 of the medical delivery system
has been inserted at least partly through the compressing
mechanism--such that the distal end 101 of the stent 100
accommodated in the compressing mechanism 10 is compressed to its
final external diameter. The final external diameter of the distal
end section 101 of stent 100 is dependent on the respective
catheter tip 105.
[0171] After the distal end section 101 of stent 100 has been
compressed to its final diameter by means of the compressing
mechanism 10, the distal end section 101 of stent 100--as shown in
FIG. 10b--is releasably affixed to the catheter tip 105.
[0172] For example, it is conceivable for the catheter tip 105--as
will be described below referencing the depictions provided in
FIGS. 12 and 13--to comprise a stent holder 150 for releasably
fixing the distal end section 101 of the stent 100. The distal end
section 101 of stent 100 compressed to its final diameter can then
be introduced into stent holder 150 (cf. FIGS. 12 and 13) by means
of the compressing mechanism 10 and fixed there.
[0173] To releasably fix the distal end section 101 of stent 100 to
the catheter tip 105, it is for example further conceivable to make
use of a first sleeve-shaped element 106 (cf. FIGS. 11a-11c) which
draws over the distal end section 101 of the stent 100 as soon as
the distal end section 101 of the stent 100 is affixed to the
catheter tip 105. The examples of the catheter tips 105-1 and 105-2
depicted in FIGS. 12 and 13 respectively provide for the distal end
section 101 of stent 100 compressed to its final diameter by means
of the compressing mechanism 10 to be introduced into the stent
holder 150 and thereafter a sleeve-shaped receiving area (first
receiving area 111) to draw over the stent holder 150.
[0174] After the compressed distal end section 101 of stent 100 is
fixed to the catheter tip 105 by means of the compressing mechanism
10, the compressing mechanism 10 is--as shown in FIG. 11c--removed
from the catheter tip 105 of the medical delivery system. To this
end, the clamping jaws 11.1-11.6 of the compressing mechanism 10
are manipulated such that the clamping jaws 11.1-11.6 are radially
moved perpendicular to the longitudinal axis of the compressing
mechanism 10 relative said compressing mechanism 10. This occurs in
that the clamping area 14 of the compressing mechanism 10 is again
rotated relative the funnel-shaped area 13, whereby however this
time the direction of rotation is different from the direction of
rotation when compressing the stent 100.
[0175] In order to also have the proximal end section 102 of the
stent 100 be compressed and be accommodated in the catheter tip 105
of the medical delivery system, the system as depicted in FIGS.
11a-11c comprises a further compressing mechanism 10'. Structurally
and functionally, this supplementary compressing mechanism 10' can
be configured similar to the compressing mechanism 10 employed in
the exemplary embodiment of the device 1 as described previously
referencing the representations of FIGS. 1 to 9b.
[0176] In order to be able to load a stent 100 into the catheter
tip 105 of a medical delivery system designed for a transapical
approach, the catheter tip 105 of the medical delivery system first
needs to be guided through the supplementary compressing mechanism
10' and thereafter through the compressing mechanism 10, within
which the already precompressed stent 100 is accommodated, as shown
in FIGS. 11a-11c. In detail, the supplementary compressing
mechanism 10' is positioned relative the compressing mechanism 10
such that the supplementary compressing mechanism 10' abuts the
proximal end section 102 of the stent 100 accommodated at least
partly inside the compressing mechanism 10.
[0177] After the compressing mechanism 10 is removed from the
catheter tip 105 of the medical delivery system--as shown in FIG.
11c--the supplementary compressing mechanism 10' is moved toward
the proximal end section 102 of the stent 100 such that at least
the proximal end section 102 of the stent 100 is accommodated at
least partly within said supplementary compressing mechanism 10'.
The proximal end section 102 of stent 100 can then be compressed,
which is done by the clamping jaws 11.1-11.6 manipulating the
supplementary compressing mechanism 10' such that said clamping
jaws 11.1-11.6 move radially relative the supplementary compressing
mechanism 10' in the direction of the longitudinal axis of said
supplementary compressing mechanism 10'. The proximal end section
102 of stent 100 thus compressed to the desired diameter can then
be accommodated in the catheter tip 105 of the medical delivery
system. For example, it is conceivable to provide at least one
second sleeve-shaped element 107 guided over the compressed
proximal end section 102 of stent 100 such that the proximal end
section 102 of stent 100 is held in its compressed form and
connected to the catheter tip 105 of the medical delivery
system.
[0178] The examples of the catheter tips 105-1 and 105-2 depicted
in FIGS. 12 and 13 respectively provide for the proximal end
section 102 of stent 100 compressed to its final diameter by means
of the supplementary compressing mechanism 10' to be kept in its
compressed state by means of a further sleeve-shaped receiving area
(second receiving area 121).
[0179] After the compressed proximal end section 102 of stent 100
is loaded for example into the second sleeve-shaped element 107 of
the catheter tip 105, the supplementary compressing mechanism 10'
is removed from the catheter tip 105 by manipulating the clamping
jaws 11.1-11.6 of the supplementary compressing mechanism 10' such
that the clamping jaws 11.1-11.6 move radially outward
perpendicular to the longitudinal axis of the supplementary
compressing mechanism 10'.
[0180] An exemplary embodiment of a catheter tip 105-1 of a medical
delivery system for transapically introducing an expanded stent
into the body of a patient will be described below referencing FIG.
12. The system described above for example with reference to FIGS.
11a-11c is suited to loading a stent 100 into the catheter tip
105-1 depicted in FIG. 12; although the disclosure is in no way
limited to the use of the system in combination with the catheter
tip 105-1 shown in FIG. 12. Rather, the following description only
serves to present an example of the design of a catheter tip 105-1
of a medical delivery system designed for a transapical approach,
whereby the system aids in loading a stent 100, as needed with a
prosthetic heart valve affixed thereto, into said catheter tip
105-1.
[0181] The catheter tip 105-1 depicted in FIG. 12 is part of a
medical delivery system (not further shown in FIG. 12) which is
suited for a transapical approach to a heart valve to be treated,
such as for example an aortic valve.
[0182] The medical delivery system enables an expandable heart
valve stent to be implanted transapically in a patient's body; i.e.
advanced from the apex of the heart. To this end, the delivery
system comprises a catheter system (not shown in FIG. 12) by means
of which the stent (likewise not depicted in FIG. 12) can be
positioned in its folded state in the patient's body.
[0183] The catheter tip 105-1 shown in FIG. 12 is disposed at the
proximal end section of the catheter system where the stent to be
implanted in the patient's body can be accommodated. A handle (not
shown in FIG. 12) can be provided at the distal end section of the
catheter system with which the catheter tip 105-1 can be
manipulated.
[0184] In detail, the catheter tip 105-1 of the medical delivery
system designed for transapical approach comprises a stent holder
150 by means of which the distal end section 101 of a stent 100 to
be implanted into the body of the patient can be releasably fixed
to the catheter tip 105-1. The catheter tip 105-1 further comprises
receiving means for receiving at least the proximal end section 102
of the stent 100. Specifically, the receiving means for the
catheter tip 105-1 exemplarly depicted in FIG. 12 consists of a
first receiving area 111 and a second receiving area 121.
[0185] As FIG. 12 indicates, the medical delivery system designed
for a transapical approach provides for the first receiving area
111 of catheter tip 105-1 to be configured as a stent sheath
connected to the proximal end tip 125 of catheter tip 105-1 with
its opening pointing toward the distal end section 126 of catheter
tip 105-1. The first receiving area 111 configured as a stent
sheath forms the outer lateral surface of the catheter tip 105-1
when the latter--as shown in FIG. 12--is in its closed state.
[0186] In the catheter tip 105-1 of the delivery system designed
for a transapical approach, the second receiving area 121 of
catheter tip 105-1 is configured as a stent funnel with its opening
pointing toward the proximal end tip 125 of catheter tip 105-1. The
proximal end section 102 of a stent 100 to be implanted (not shown
in FIG. 12) can for example be received within the second receiving
area 121 configured as a stent funnel after the system has been
used--as described above referencing FIGS. 11a-11c--to compress the
proximal end section 102 of stent 100 accordingly.
[0187] For example, it is conceivable for the proximal end section
102 of stent 100 to comprise retaining holders to which a
prosthetic heart valve is affixed as needed. In such a case, the
retaining holders of stent 100, and the prosthetic heart valve
affixed as needed to the retaining holders, are accommodated within
the second receiving area 121 of catheter tip 105-1 configured as a
stent funnel.
[0188] In the closed state of catheter tip 105-1 (cf. FIG. 12), the
second receiving area 121 con-figured as a stent funnel is
telescopically received by the first receiving area 111 configured
as a stent sheath, whereby positioning holders of the stent can for
example be arranged between the outer lateral surface of the stent
funnel and the inner lateral surface of the stent sheath when a
corresponding heart valve stent is accommodated in the catheter tip
105-1.
[0189] In the catheter tip 105-1 of a medical delivery system
designed for a transapical approach as depicted in FIG. 12, the
second receiving area 121 of the catheter tip 105-1 is--as noted
above--configured as a stent funnel in the form of a tubular or
sleeve-like element. The stent funnel (second receiving area 121)
can be connected to actuating means of a handle via a force
transfer means (not explicitly shown in FIG. 12) so that pulling or
pushing forces can be transferred to the second receiving area 121
of the catheter tip 105-1 upon the actuating of the actuating
means. In this way, the second receiving area 121 of the catheter
tip 105-1 configured as a stent funnel can be displaced in the
longitudinal direction of the catheter tip 105-1 relative the stent
holder 150 on the one hand and, on the other, the first receiving
area 111 configured as a stent sheath.
[0190] As indicated above, it is preferred for the first receiving
area 111 of the catheter tip 105-1 of the medical delivery system
designed for a transapical approach to be configured as a stent
sheath, for example in the form of an elongated tube. The second
receiving area 121 is preferably configured as a stent funnel,
likewise for example in the form of an elongated tube. The inner
diameter of the tubular or sleeve-shaped first receiving area 111
should thereby be selected to be larger than the outer diameter of
the likewise tubular or sleeve-shaped second receiving area 121
such that the second receiving area 121 can be telescopically
received inside the first receiving area 111.
[0191] The stent holder 150 of the catheter tip 105-1 for a medical
delivery system designed for a transapical approach as depicted in
FIG. 12 is configured as a cylindrical element furnished with
appropriate retaining elements 151. The retaining elements 151
serve to create a releasable connection to a retaining section of a
heart valve stent 100 not shown in FIG. 12 when the stent 100 is
accommodated in the catheter tip 105-1. Conceivable here would be
to configure the retaining elements 151 of the stent holder 150
such that they can releasably engage with the retaining elements of
stent 100.
[0192] In FIG. 12, the retaining elements 151 of stent holder 150
are for example configured as projecting elements which can be
brought into engagement with retaining grommets of a stent 100
configured correspondingly complementary thereto. It would however
also be conceivable for the retaining elements 151 of stent holder
150 to be configured as cavities or recesses introduced into the
cylindrical body of the stent holder 150 and designed to receive
correspondingly complementary configured retaining elements of the
heart valve stent 100.
[0193] The procedure for loading a heart valve stent 100 into the
example of the catheter tip 105-1 as depicted in FIG. 12
corresponds to the method described above with reference to the
representations of FIGS. 11a-11c. To avoid repetition, the loading
procedure will not be reiterated in detail here; reference is
instead made to the previous remarks.
[0194] With the catheter tip 105-1 for a medical delivery system
designed for a transapical approach shown as an example in FIG. 12,
the stent holder 150 is arranged to be stationary relative the (not
shown) handle of the medical delivery system such that upon a
rotation of the handle about the longitudinal axis of the medical
delivery system, for example, the stent holder 150 will also be
engaged in the rotational motion. It is hereby conceivable for the
stent holder 150 to be connected to the handle via connecting means
fixedly attached to the body of the handle.
[0195] On the other hand, the first receiving area 111 of the
catheter tip 105-1 is also movable in the longitudinal direction of
the catheter tip 105-1 relative the stent holder 150 by means of
appropriately manipulating a force transfer means. With the
catheter tip 105-1 shown for example in FIG. 12, an inner catheter
130 configured as a cannula tube extending from a distal end
section of a handle (not shown in FIG. 12) to the proximal-side end
tip 125 of the catheter tip 105-1 is employed as the force transfer
means.
[0196] As indicated above, it is provided in the case of the
catheter tip 105-1 for a medical delivery system designed for a
transapical approach for the stent holder 150 of the catheter tip
105-1 to preferably be fixedly connected to a handle, a body of the
handle respectively, so as to in particular freeze the freedom of
rotational motion about the longitudinal axis of the medical
delivery system respective the stent holder 150 as well as the
freedom of motion in the direction of the longitudinal axis of the
medical delivery system. Accordingly, the stent holder 150 is
restricted from moving at least in the longitudinal direction of
the medical delivery system relative the body of the handle.
Rotational motion of the stent holder 150 about the longitudinal
axis relative the handle is likewise eliminated.
[0197] It is to be emphasized that the system for loading a stent
100, as needed with a prosthetic heart valve 100 affixed thereto,
into the tip of a catheter of a medical delivery system as
disclosed above based on the example referencing FIGS. 11a-11c is
not only applicable to a catheter tip 105-1 for a medical delivery
system designed for a transapical approach. In fact, it is equally
possible to also use the system to load a stent system into a
catheter tip of a medical delivery system designed for a trans
femoral/transarterial approach.
[0198] The following, referencing FIG. 13, will describe the design
of an exemplary embodiment of a catheter tip 105-2 of a medical
delivery system designed to transfemorally /transarterially
introduce an expandable stent into the body of a patient. To be
considered here is that the previously-described example of a
system referencing FIGS. 11a-11c is also suited to load a stent 100
into the catheter tip 105-2 depicted in FIG. 13. The following
description serves to present an example of a catheter tip 105-2 of
a medical delivery system designed for a transfemoral/transarterial
approach, whereby the system can be employed to load a stent, as
needed with a prosthetic heart valve affixed thereto, into said
catheter tip 105-2.
[0199] The catheter tip 105-2 depicted in FIG. 13 is part of a
medical delivery system (not further shown) applicable for
transfemorally/transarterially approaching a heart valve to be
treated such as an aortic valve, for example. The medical delivery
system enables an expandable heart valve stent to be implanted into
the body of a patient transfemorally or transartially, i.e. from
the aortic arch. To this end, the delivery system comprises a
catheter system (not shown in FIG. 13), by means of which the heart
valve stent (likewise not shown in FIG. 13) can be introduced into
the body of the patient in its folded state.
[0200] The embodiment of the medical delivery system suited for a
transarterial or transfemoral approach differs from the delivery
system designed for transapical approach as described above
referencing the FIG. 12 representation by the catheter tip 105-2
exhibiting a modified design to allow the transarterial approach to
the site of implantation.
[0201] With regard to the design of the catheter tip 105-2 allowing
the transarterial or transfemoral approach for the stent
accommodated in the catheter tip 105-2 to the site of implantation,
it can be seen from FIG. 13 that the catheter tip 105-2--just like
the catheter tip 105-1 of the delivery system designed for a
transapical approach--comprises a stent holder 150 for releasably
fixing for example the distal end section 101 of a stent 100 which
can be accommodated in the catheter tip 105-2. Compared to the
catheter tip 105-1 for the delivery system designed for a
transapical approach, the retaining elements 151 of the stent
holder 150 configured as a crown are here provided at the distal
end of the stent holder 150.
[0202] Furthermore, the catheter tip 105-2 of the delivery system
designed for a transarterial/transfemoral approach comprises
receiving means to receive a heart valve stent with the prosthetic
heart valve affixed thereto as needed. Specifically, the receiving
means of the catheter tip 105-2 consists of a first receiving area
111 to receive the distal end section 101 of a stent 100, in
particular the positioning holder of a stent, and a second
receiving area 121 to receive the proximal end section 102 of the
stent 100, in particular the retaining holder of the stent with the
prosthetic heart valve affixed thereto as needed.
[0203] As distinguished from the catheter tip 105-1 of the medical
delivery system designed for a transapical approach as described
with reference to FIG. 12, in the catheter tip 105-2 of the medical
delivery system designed for a transarterial/transfemoral approach
pursuant FIG. 13, the second receiving area 121 (stent funnel)
serving to receive the proximal end section 102 of the stent 100,
and in particular the retaining holder of the stent with the
prosthetic heart valve affixed as needed thereto, is arranged on
the proximal end section 125 of the catheter tip 105-2 while the
first receiving area 111 (stent sleeve) is arranged between the
second receiving area 121 and a handle (not shown in FIG. 13).
[0204] In the catheter tip 105-2 of the medical delivery system as
depicted in FIG. 13 designed for the transarterial approach to an
insufficient or stenosed native heart valve, it is preferable to
configure force transfer means, which connect actuating means of
the handle to the second receiving area 121 (stent funnel) of the
catheter tip 105-2, as an inner catheter 131 extending through the
interior of an outer catheter or a sheath system. A further force
transfer means which connects further actuating means of the handle
to the first receiving area 111 (stent sleeve) of the catheter tip
105-2, is configured as an outer catheter, through the interior of
which runs the other force transfer means configured as the inner
catheter.
[0205] Upon the actuating of the associated actuating means, the
second receiving area 121 (stent funnel) is movable in the
longitudinal direction of the catheter tip 105-2 relative the stent
holder 150 in the proximal direction; i.e. away from the (not
shown) handle, while the first receiving area 111 of catheter tip
105-2 is movable, upon the actuating of the correspondingly
associated actuating means of the handle, in the longitudinal
direction of the catheter tip 105-2 relative stent holder 150 in
the distal direction; i.e. toward the handle not shown in FIG.
13.
[0206] The manipulations of the respective receiving areas 111, 121
of the catheter tip 105-2 of the delivery system designed for a
transarterial/transfemoral approach effected by the actuating of
the respective actuating means enables a sequential release of a
stent 100 accommodated in the catheter tip 105-2, preferably at the
site of implantation in the patient's heart.
[0207] The procedure for loading a heart valve stent 100 into the
catheter tip 105-2 depicted as an example in FIG. 13
corresponds--at least in principle--to the method described above
with reference to the representations of FIGS. 11a-11c.
[0208] In order to be able to load a stent 100 into the catheter
tip 105-2 of a medical delivery system designed for a
transfemoral/transarterial approach, however, it is necessary to
insert the catheter tip 105 of the medical delivery system through
the compressing mechanism 10, within which the already
precompressed stent 100 is accommodated. The distal end section 101
of the stent 100 can then be further compressed and brought into
engagement with the stent holder 150 of the catheter tip 105-2. The
compressing mechanism 10 can thereafter be removed from the
catheter tip 105-2 of the medical delivery system. The
supplementary compressing mechanism 10' is then employed, or the
previously used compressing mechanism 10 also previously removed
from the catheter tip 105-2 can also be re-employed, in order to
compress the proximal end section 102 of the stent 100 accordingly.
As is also the case in the loading procedure for a catheter tip
designed for a transapical approach (cf. FIG. 12), the compressing
mechanism 10, supplementary compressing mechanism 10' respectively,
is thereby to be positioned such that the compressing mechanism 10,
supplementary compressing mechanism 10' respectively, at least
partly abuts the proximal end section 102 of the stent 100 at least
partly accommodated within the compressing mechanism 10. The
compressing of the proximal end section 102 of the stent 100 can
then ensue, done so by the clamping jaws 11.1-11.6 of the
compressing mechanism 10, the supplementary compressing mechanism
10' respectively, being manipulated such that the clamping jaws
11.1-11.6 are moved radially relative to the compressing mechanism
10, the supplementary compressing mechanism 10' respectively. The
proximal end section 102 of stent 100 so compressed to the desired
diameter can then be accommodated in the catheter tip 105-2 of the
medical delivery system.
[0209] In summary, it remains to be noted that the above disclosure
transforms a stent, as needed with a prosthetic heart valve affixed
thereto, from its expanded state into a compressed state in
particularly smooth manner. The above disclosure is not only suited
to compressing stents, but also grasping a stent in the catheter
tip of a transapical or transfemoral medical delivery system. The
degree of compression is adjustable at will.
[0210] The disclosed solution is not limited to the embodiments
described with reference to the accompanying drawings. Also just as
conceivable in fact are combinations of the individual features as
specifically described.
[0211] A device (1) for compressing a stent (100) or--if
required--a stent (100) with a prosthetic heart valve affixed
thereto, wherein the device (1) comprises the following: [0212] a
compressing mechanism (10), within which a stent (100) to be
compressed can be at least partly accommodated, wherein the
compressing mechanism (10) is designed so as to exert a defined
compressive force in radial direction on at least parts of a stent
(100) to be compressed accommodated within the compressing
mechanism (10) such that the cross-section of the stent (100) is
reduced to a predefinable value at least at certain areas; and
[0213] a gripping mechanism (20) to form a releasable connection
with a stent (100) to be compressed, in particular with a distal
end section (101) of said stent (100) to be compressed, wherein the
gripping mechanism (20) is displaceable within the compressing
mechanism (10) in the longitudinal direction relative said
compressing mechanism (10) to be at least partly accommodated and
an actuating element (21) is provided which is allocated a claw
(22) to grasp the stent (100) to be compressed, and wherein the
compressing mechanism (10) comprises at least one
externally-manipulatable clamping jaw (11.1, 11.2, 11.3, 11.4,
11.5, 11.6) which is movable in the radial direction to adjust the
internal cross-sectional diameter of the compressing mechanism
(10).
[0214] Wherein the gripping mechanism (20) comprises a guide sleeve
(23) in which the claw (22) can be at least partly
accommodated.
[0215] Wherein the diameter exhibited by the stent (100) after its
compression effected by the device (1) is definable by an internal
diameter of the guide sleeve (23).
[0216] Wherein the claw (22) is movable relative the guide sleeve
(23) upon actuating of the actuating element (21).
[0217] Wherein the guide sleeve (23) comprises at least one guiding
element (24) configured complementary to the at least one guiding
element (12) allocated to the compressing mechanism (10).
[0218] Wherein the at least one guiding element (24) allocated to
the guide sleeve (23) is configured as a guide rail.
[0219] Wherein the gripping mechanism (20) comprises a retaining
section (25) arranged coaxially to the guide sleeve (23) and
connected to said guide sleeve (23).
[0220] Wherein the actuating element (21) comprises a preferably
manually-actuatable pushbutton (26) accommodated in the retaining
section (25) and movable in the longitudinal direction of the
gripping mechanism (20) relative the guide sleeve (23).
[0221] Wherein the claw (22) comprises at least one and preferably
three gripper arms (27.1, 27.2, 27.3) wherein fastening means
(28.1, 28.2) are preferably provided on the first end section of
the at least one gripper arm (27.1, 27.2, 27.3) to create a
releasable connection with a stent (100) to be compressed, in
particular with a distal end section (101) of the stent (100) to be
compressed.
[0222] Wherein the fastening means (28.1, 28.2) provided on the at
least one gripper arm (27.1, 27.2, 27.3) are configured to be
complementary to a retaining section or complementary to a
retaining element of the stent (100) to be compressed, in
particular such that the fastening means (28.1, 28.2) are designed
to form a releasable engagement with the retaining section of the
stent (100) to be compressed.
[0223] Wherein the fastening means (28.1, 28.2) provided on the at
least one gripper arm (27.1, 27.2, 27.3) comprise at least one
projecting element (28.1) which can be brought into releasable
engagement with a retaining grommet of a stent (100) to be
compressed designed to be correspondingly complementary
thereto.
[0224] Wherein the fastening means (28.1, 28.2) provided on the at
least one gripper arm (27.1, 27.2, 27.3) exhibit at least one
recess (28.2) configured in the first end section of said gripper
arm (27.1, 27.2, 27.3), in particular in the form of a preferably
oblong grommet, which can be brought into releasable engagement
with a projecting retaining element of a stent (100) to be
compressed designed complementary thereto.
[0225] Wherein the at least one gripper arm (27.1, 27.2, 27.3)
comprises the fastening means (28.1, 28.2) at its first end section
and is connected to the fastening element (21) of the gripping
mechanism (20) by its opposite second end section.
[0226] Wherein the claw (22) comprises a guide shaft (20), wherein
the first end section (29a) of the guide shaft (29) is connected to
the second end section of the at least one gripper arm (27.1, 27.2,
27.3) and the second end section (29b) of the guide shaft (29) is
connected to the actuating element (21) of the gripping mechanism
(20).
[0227] Wherein the guide shaft (29) is accommodated within the
guide sleeve (23) such that said guide shaft (29) is displaceable
relative the guide sleeve (23) together with the at least one
gripper arm (27.1, 27.2, 27.3) connected thereto.
[0228] Wherein guide means (30) are provided to guide the guide
shaft (29) within the guide sleeve (23).
[0229] Wherein the at least one gripper arm (27.1, 27.2, 27.3) is
connected to the guide shaft (29) via its second end section such
that the at least one gripper arm (27.1, 27.2, 27.3) protrudes from
the guide shaft (29)--relative to the longitudinal direction of
said guide shaft (29)--at an angle.
[0230] Wherein the at least one gripper arm (27.1, 27.2, 27.3)
and/or the connecting area (33) between the second end section of
the at least one gripper arm (27.1, 27.2, 27.3) and the first end
section (29a) of the guide shaft (29) is/are configured so as to be
elastically deformable such that upon a displacement of the guide
shaft (20) relative the guide sleeve (23), the at least one gripper
arm (27.1, 27.2, 27.3) connected to the guide shaft (29) can be at
least partly accommodated in the guide sleeve (23) by simultaneous
radial deformation.
[0231] Wherein gripping mechanism (20) comprises a spring mechanism
which interacts with the claw (22) such that the claw (22) can be
spring-locked.
[0232] Wherein the spring mechanism comprises a spring (31), in
particular a helical compression spring, arranged in the retaining
section (25) of the actuating element (21) such that it pretensions
the pushbutton (26) of the actuating element (21) against the guide
sleeve (23).
[0233] Wherein the pretensioning exerted by the spring (31) on the
pushbutton (26) of the actuating element (21) is selected such that
without on the one hand impacting the compressive force exerted
externally on the pushbutton (26), the claw (22)--with the
exception of the fastening means (28.1, 28.2) provided at the first
end section of the at least one gripper arm (27.1, 27.2, 27.3)--is
accommodated completely within the guide sleeve (23).
[0234] Wherein the stroke of the spring (31) is shorter than the
length of the at least one gripper arm (27.1, 27.2, 27.3).
[0235] Wherein the compressing mechanism (10) comprises a
funnel-shaped area (13) at least at one end, and wherein the
compressing mechanism (10) further comprises a clamping area (14)
aligned coaxially to the funnel-shaped area (13) and connected to
said funnel-shaped area (13), and in which the at least one
clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is
accommodated.
[0236] Wherein the compressing mechanism (10) comprises a
tensioning screw accommodated in the clamping area (14) which is
rotatable about the longitudinal axis of the compressing mechanism
(10) relative the at least one clamping jaw (11.1, 11.2, 11.3,
11.4, 11.5, 11.6) and which interacts with the at least one
clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) such that upon a
rotation of the tensioning screw, the at least one clamping jaw
(11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is displaced in the
longitudinal direction of the compressing mechanism (10) relative
to a clamping cone accommodated in the clamping area (14).
[0237] Wherein the compressing mechanism (10) comprises a
tensioning screw accommodated in the clamping area (14) which is
movable along the longitudinal axis of the compressing mechanism
(10) relative the at least one clamping jaw (11.1, 11.2, 11.3,
11.4, 11.5, 11.6), and which interacts with the at least one
clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) such that upon a
translational displacement of the tensioning screw, the at least
one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is displaced
in the longitudinal direction of the compressing mechanism (10)
relative to a clamping cone accommodated in the clamping area
(14).
[0238] Wherein the at least one clamping jaw (11.1, 11.2, 11.3,
11.4, 11.5, 11.6) interacts with the clamping cone such that upon a
movement of the at least one clamping jaw (11.1, 11.2, 11.3, 11.4,
11.5, 11.6) into the clamping cone, the at least one clamping jaw
(11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is moved in the radial
direction.
[0239] Wherein the clamping area (14) is rotatable about the
longitudinal axis of the compressing mechanism (10) relative the at
least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) and
interacts with the at least one clamping jaw (11.1, 11.2, 11.3,
11.4, 11.5, 11.6) such that the at least one clamping jaw (11.1,
11.2, 11.3, 11.4, 11.5, 11.6) moves in the radial direction upon a
rotation of the clamping area (14).
[0240] Wherein the clamping area (14) is configured as a hollow
cylinder exhibiting varying wall thicknesses along its periphery,
wherein the at least one clamping jaw (11.1, 11.2, 11.3, 11.4,
11.5, 11.6) abuts the inner lateral surface of the clamping area
(14) configured as a hollow cylinder such that when the clamping
area (14) is rotated relative the at least one clamping jaw (11.1,
11.2, 11.3, 11.4, 11.5, 11.6), the at least one clamping jaw (11.1,
11.2, 11.3, 11.4, 11.5, 11.6) is moved--in dependence on the wall
thickness of the hollow cylinder in the contact area with the at
least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6)--in the
radial direction.
[0241] Wherein the clamping area (14) is rotatable about the
longitudinal axis of the compressing mechanism (10) relative the
funnel-shaped area (13).
[0242] Wherein the clamping area (14) is movable along the
longitudinal axis of the compressing mechanism (10) relative the at
least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) and
interacts with the at least one clamping jaw (11.1, 11.2, 11.3,
11.4, 11.5, 11.6) such that the at least one clamping jaw (11.1,
11.2, 11.3, 11.4, 11.5, 11.6) moves in the radial direction upon a
translational displacement of the clamping area (14).
[0243] Wherein the clamping area (14) is configured as a hollow
cylinder exhibiting varying wall thicknesses along its periphery,
wherein the at least one clamping jaw (11.1, 11.2, 11.3, 11.4,
11.5, 11.6) abuts the inner lateral surface of the clamping area
(14) configured as a hollow cylinder such that when the clamping
area (14) is shifted along the longitudinal axis of the compressing
mechanism (10) relative the at least one clamping jaw (11.1, 11.2,
11.3, 11.4, 11.5, 11.6), the at least one clamping jaw (11.1, 11.2,
11.3, 11.4, 11.5, 11.6) is moved--in dependence on the wall
thickness of the hollow cylinder in the contact area with the at
least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6)--in the
radial direction.
[0244] Wherein the clamping area (14) is movable along the
longitudinal axis of the compressing mechanism (10) relative the
funnel-shaped area (13).
[0245] A system for loading a stent (100) or--if required--a stent
(100) with a prosthetic heart valve affixed thereto into a medical
delivery system, in particular a catheter tip (105) of a medical
delivery system, wherein the system comprises a device (1) in
accordance with any one of the preceding claims and a supplementary
compressing mechanism (10') for compressing the proximal end
section (102) of the stent (100), wherein the supplementary
compressing mechanism (10') is configured analogously to the
compressing mechanism (10) of the device (1) in accordance with any
one of the preceding claims.
[0246] The use of a device according to any one of claims 1 to 32
or a system according to claim 33 for loading a stent (100) or--if
required--a stent (100) with a prosthetic heart valve affixed
thereto into a medical delivery system, in particular into a
catheter tip (105) of a medical delivery system.
[0247] A method for loading a stent (100) or--if required--a stent
(100) with a prosthetic heart valve affixed thereto into a medical
delivery system, in particular into a catheter tip (105) of a
medical delivery system, wherein the method comprises the following
method steps: [0248] i) furnishing a device (1) in accordance with
any one of claims 1 to 32 or a system in accordance with claim 33;
[0249] ii) connecting the gripping mechanism (20) to the
compressing mechanism (10) such that the gripping mechanism (20) is
at least partly accommodated in the compressing mechanism (10)
configured as a hollow cylinder; [0250] iii) grasping the stent
(100) by appropriately actuating the actuating element (21) so as
to form a releasable connection between a distal end section (101)
of the stent (100) and the claw (22) of the gripping mechanism
(20); [0251] iv) precompressing the stent (100) by moving the
gripping mechanism (20) in the longitudinal direction relative the
compressing mechanism (10) such that the stent (100) is at least
partly accommodated within the compressing mechanism (10)
configured as a hollow cylinder; [0252] v) disengaging the gripping
mechanism (20) from the stent (100) by appropriately actuating the
actuating element (21) such that the claw (22) of the gripping
mechanism (20) moves relative to said gripping mechanism (20) and
the connection between the distal end section (101) of stent (100)
and the claw (22) is disengaged; [0253] vi) compressing at least
the distal end section (101) of stent (100) by manipulating the at
least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) such
that said at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5,
11.6) is moved radially perpendicular to the direction of the
longitudinal axis of the compressing mechanism (10); and [0254]
vii) inserting the compressed distal end section (101) of stent
(100) into a first sleeve-shaped element (106) of the catheter tip
(105) of the medical delivery system.
[0255] Wherein prior to the manipulation of the at least one
clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) in method step
vi), at least one area of the catheter tip (105) of the medical
delivery system is guided through the compressing mechanism (10)
configured as a hollow cylindrical body.
[0256] Wherein at least one area of the catheter tip (105) of the
medical delivery system is guided through a supplementary
compressing mechanism (10') configured as a hollow cylindrical body
such that the supplementary compressing mechanism (10') abuts the
proximal end section (102) of the stent (100) at least partly
accommodated within the compressing mechanism (10).
[0257] Wherein the method comprises the following method steps
subsequent the introduction of the compressed distal end section
(101) of stent (100) in a first sleeve-shaped element (106) of the
catheter tip (105) of the medical delivery system in method step
vii): [0258] viii) manipulating the at least one clamping jaw
(11.1, 11.2, 11.3, 11.4, 11.5, 11.6) of compressing mechanism (10)
such that the at least one clamping jaw (11.1, 11.2, 11.3, 11.4,
11.5, 11.6) is moved outwards radially to the longitudinal axis of
the compressing mechanism (10) relative said compressing mechanism
(10); [0259] ix) removing the compressing mechanism (10) from the
catheter tip (105) of the medical delivery system; [0260] x) moving
the supplementary compressing mechanism (10') toward the proximal
end section (102) of the stent (100) such that at least the
proximal end section (102) of the stent (100) is accommodated at
least partly within the supplementary compressing mechanism (10')
configured as a hollow cylindrical body; [0261] xi) compressing at
least the proximal end section (102) of stent (100) by manipulating
the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6)
of supplementary compressing mechanism (10') such that the at least
one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is moved
inwards radially relative to the supplementary compressing
mechanism (10') in the direction of the longitudinal axis of said
supplementary compressing mechanism (10'); and [0262] xii)
introducing the compressed proximal end section (102) of stent
(100) into at least one second sleeve-shaped element (107) of the
catheter tip (105) of the medical delivery system.
* * * * *